i drive an f150 with the coyote engine, about 900 pounds of aftermarket stuff (winch, bumpers, crane, camper top) i need for work. i replaced the stock firestones with 33" ko2's inflated to 50 psi because i kept puncturing the sidewalls of the firestones when driving out in the paddock. you people all hate me because on the freeway im the guy doing 45-50 mph in the right lane. if i never leave the farm, my mileage is 16.5 give or take .2 mpg. if i spend half my time on the freeway, 17.2 ish. if i spend a whole tank on the freeway 18.5. towing a trailer of any weight drops it back to 17.2ish. if you want to save fuel, you'd be better served to simply drive slower. it saves a lot of money and costs you a little time but its up to you which is more important.
The larger tyres will up your gear ratio, it will slow down your acceleration and use more fuel to do that but once your up to speed you will use less fuel, the lower RPM is the confirmation of this. The KO's are the best compromise for on/off road and last a very long time so they save you money there
KO's "last a very long time"? Well I had the KO1's factory installed on my 2013 Ford Raptor. Not abusing it, not hauling anything and not doing stupid TH-cam Raptor showoffs stuff - mainly driving on normal roads, rarely dirt roads. And the KO1's did not pass inspection after only 19K miles. Now I have the KO2's and have about 11K miles on them. Will see how long they will last. I doubt they will do better than the predecessors. FYI: The KO's do NOT last a very long time for sure - believe me - and I am very disappointed as I was expecting at least 27-30K on them.
The vehicle is engineered to work best as it come out of the factory line - change the tire diameter and you will be messing up the speedometer which in turn will affect transmission gear up/down points and also mess with torque tolerances on transmission/axes - you might gain a few miles per gallon on FLAT terrain and lose on hills as it will be needing more HP than before do to larger tires.
@@gt-c- I think one’s driving habits affect tire wear. I have the e-rated KO2’s on the Tacoma and keep 45lbs of air in them unless I’m off-road. But, unlike your truck, my Tacoma doesn’t have the get up and go your truck has. And, I could careless how many seconds it takes me to get up to 60mph. I go easy on the gas and easy on the brakes. I don’t drive fast, only about 62-65 on interstate. I still have original rear brakes and replaced the front pads at 120k just because I thought I ought to. They still had life left in them. I expect to get at least 60k out of this set of tires as well. I’ve got 30,000 on them now and they still look great.
@@jimandvalstravelchannel Thank you for the feedback. In addition to what I already mentioned above: I do not abuses this truck, do not break hard, do not do donots, do not drive aggressive, do not go above 70-75 mph and do not burn rubber. It is a big truck (a tank) I agree, almost twice the weight of a Tacoma, but still considering all of these conditions,,,the KO's should have lasted more.
There is definitely a lot of things acting for and against better MPG here. Taller tires, on nothing but highway use, will get you better gas mileage, but they have to be the same or even narrower tire size. Rolling resistance is what’s offsetting the gains you get with the larger diameter tire. Especially when going to a more aggressive non-highway tread. Once you start to do quite a bit of city driving, especially stop and go, this is where you lose drastically with a taller tire. So if you did more, or more aggressive city driving, and less time on the highway, you’re going to see a lot worse gas mileage. Although, if you have a trip planned, that’s gonna take you 90% on the highway, the taller (and not overly wide with highway tread) tire will definitely be best. Not just for fuel economy, but for other factors as well.. if the tire is an aggressive tire, it will be just like what they experience with their test. Maybe in the future, we will have tires that expand from the center of the tire while decreasing the tire width tremendously to reduce rolling resistance. Then go back down to smaller diameter tires for city Drive. Or we ditched Tires all together and just disco with flying cars.
You can use an OBD tool to see actual real time fuel economy. The tool and associated software can see how much fuel is going through the injectors. The Everlanders use a similar device but I can't remember the brand
Awesome video, have the same van but the NA engine and consistently get about 18 mpg. Was wondering how the larger tires would affect it so now i know. In my opinion whats killing your mpg is that roof rack acting like a parachute. Keep up the interesting and informative videos! 👍
How was the ride? That would be an interesting comparison. Quite a challenge to set up criteria. I would think that a narrower tire would get better gas milage considering less friction and resistance.
Yeah, you're pushing 9,000 lbs around, so it's not surprising. I'm wondering how much weight could really be saved by using light materials, honeycomb panes, etc.
Okay, maybe my van doesn’t count as “full build out” I don’t have a bathroom or shower. And I don’t store 100 liters of water. BUT my 2019 sprinter LWB gets 18 to 21.
3 factors (minor) that you didn’t mention are tire and wheel weight, width, and the fact that the aftermarket wheels lift the van creating slightly more wind resistance. I have an Escape with 2.0 eco boost with a small lift and upsized Wranglers and the biggest difference is IN MY HEAD as the display shows average mpg about 10% lower than it used to. Of course I didn’t recalibrate Speedo so makes perfect sense. I also notice a little wind noise from under the front end now and suspect the air under the car is more turbulent.
Two thoughts 💭 1. Wind! By any chance, do you know if wind changed? Even 5mph tailwind change into headwind is enough to cause a 2mpg increase for me. 2. Lower RPM! Like you mentioned it change from 1700 to 1900. Could slightly affect your mpg too; although not as much as I would expect from headwind/tail wind.
What is the weight difference between those wheel/tire sets? This could greatly affect your mpg. Once the heavy tires are rolling, extra weight requires less energy to keep it moving. But heavier tires take more to get them going. 45 miles is a good start but your 1/4 gal diff would be a full gallon at 200 miles and depending on tank size and normal miles per tank, you could be at 1.5 gallon diff per tank
The Ford 3.5L Eco-boost is notorious for gas guzzling when you drive the twin turbos… And acceleration or in towing. You can help that by avoiding a “lead-foot”!
Great analysis! Awesome van! We have same van (not nearly as cool) and we did notice a loss of MPG at speeds over 65 MPH and it progressively gets worse as you approach 80 mph (we went from Vanco stock 255 75 16) . Our van is a medium roof, but the tires gaves us almost 1.5" lift as it now barely fits in our garage. When our van tires were brand new our speedometer was off by 5 miles (6 at over 67 mph according to GPS). Our van is a 2017 and we get an average of 15/16 mixed city/hwy. We keep our speeds under 65 MPH and try to stay around 50 MPH on lonely roads and we can get up to 19 MPG (I GPS from gas station to gas station and use the miles driven/gallons pumped). Thanks again!!!!
From your video a month ago, you were getting 12mpg. Now you are improved to 14+mpg. Soon, it’ll be 15, 16, and 17mpg. As my Transit Ecoboost engine broke in, exact same numbers. There seemed to be a more pronounced increase after the first oil change. Likely the break-in oil from the factory is thicker. I still have pretty low mileage on my van, but I just got over 17mpg on two consecutive round trips from Santa Cruz to the Sierra Nevada mountains and back (twice, to be redundant). Frankly, I was very concerned at 12mpg when I first got the van. At 16mpg, I felt relieved. Now at 17mpg, it’s not bad at all. (Makes me pleased I didn’t spend for the diesel Sprinter.) I’m not sure I’ll get to 18mpg or even 19mpg, but that would be fantastic!!! As you know, gasoline here in California is pretty expensive, and it hasn’t come down from the peak hardly at all (contrary to what the media is reporting about -$1 for the national average). Anyway, be patient and I expect you’ll be rewarded. BTW, I ordered my Transit with the 31 gallon tank, and that is a nice feature. The extra range makes it easier to buy gas at lower priced stations.
I actually just changed the oil about 1500 miles ago and it’s been getting better - however we also took the motorcycle off the back and removed the running boards so we lost some air drag plus about 500 lbs
@@Weretherussos Driving style also helps mileage. I tend to get higher mileage than my wife, for example. I always beat the EPA estimate on every car. I get off the gas pedal sooner and coast. Drive like you are trying to avoid using the brake pedal. I don’t accelerate super fast or super slow - just normal. But I keep a reasonable following distance and look farther up the road for red lights, slow-downs, etc., thereby using the brakes less often. Gas has energy. You put the energy into motion. Your vehicle’s motion has potential energy. Then you brake and throw away all that energy by converting it to heat in your pads and rotors, which dissipates to the air (causing global warming, LOL). By using your brakes less, you are being environmentally conscientious. The result is manifested when you buy slightly less gas. The other way to think about it is don’t put more gas into your engine (via the pedal) than you need.
@@Weretherussos To reduce air drag, I put expensive CIGS flexible solar panels on my van’s roof. Unfortunately, they have delaminated, so I bought a rack and some glass panels. The rack is low profile and comes with a faring, so hopefully it won’t hurt mileage too much. We’ll see after I install it.
Very interesting and I look forward to the next installment. There are 2 other questions I hope you answer. 1) how does each set of tire differ in handling, and road noise; interstate, 2 lane highway and off highway driving. I’ve been debating for a while if I want a more aggressive tire. I assume there is a lift on your van, was there any sheet metal removal in order to accommodate the larger tires?
Answer is already available by looking at electric cars that offer multiple tire sizes. Ranges are lowered with the larger tires. It’s all the same physics regardless of whether your fuel is electrons or petrol. This is only true within a reasonable range - get too tiny on the wheel size and other problems occur.
It does change the drag coefficient and yes it does affect gas mileage. Says Tesla and Aptera who both have done extensive testing. However you don’t wish to get stuck so It may be worth it depending on how rough the places you go.
I think you experimental design was right on (same pump, exact same route at the same speeds). Your comparison numbers are what I would expect based on similar comparisons made over the years in my vehicles. I would expect larger wheels with the same tread design to be equal. And I suspect that the lower MPG for your KO2s might be a result of the more open tread pattern and higher rolling resistance. (There are alot of us Dave Johnsons ;-))
I suspect that tire size is going to have a fairly limited effect on your fuel economy. Larger tires require more torque to turn to provide acceleration and maintain speed against wind resistance. Since your transmission has not changed (and the engineers have engineered your car for a specific tire size) you will consume more fuel to achieve the same acceleration and fight any forces that are trying to slow down the car (wind resistance, road friction, gravity). This is a net negative. But, larger tires will run the engine at a lower rpm on the freeway. This is a net positive. Finally, having an aggressive tread will result in more of your fuel being turned into tire heat vs. forward motion. Once again, a net negative. These might cancel each other out depending on your driving style and where you are going. But... all of that is probably swamped by wind resistance. With a large, fairly un-aerodynamic shape, most of your fuel is burned fighting the wind. When that is the case, the slight difference that you would experience from the bigger or smaller tires would become a tiny fraction of the overall fuel consumption. Consider an extremely efficient car (like, say, an Aptera). Since this car is very aerodynamic, a smaller percentage of its fuel consumption is used to fight wind resistance. That means any factors that affect OTHER aspects of its fuel consumption (like road friction or acceleration or fighting gravity) will have a proportionally larger affect on its overall efficiency. So tires might actually change these numbers a fair bit. Since a van is essentially a giant brick trying to move through the air, a much larger percentage of its energy is used up fighting wind resistance (which goes up as the square of speed, so doubling your speed will result in a 4x increase in resistance). That means the percentage that is used in ways that your tires have an effect on (acceleration, rolling resistance, etc.) will have less of a proportional effect. BUT... One other thing to keep in mind is that the way we think about fuel economy in North America is kind of backwards. We think of it in terms of miles per gallon, which hides proper comparisons behind a non-intuitive way of looking at the numbers. Say you have a truck that gets 10 mpg and a car that gets 90 mpg. If you had the option of replacing the truck with another truck that gets 20 mpg OR replacing the car with another car that gets 100 mpg... you should replace the truck, even though both vehicles are improving on their predecessor by 10 mpg. The reason is if you replace the truck, you will use 50% less fuel (for the same distance travelled). If you replace the car, you will only use 10% less fuel. You have to think of it in terms of percentages, not in terms of mpg improvements. So IF you find out that smaller tires actually DO improve your mileage by 1 mpg (just to pull a number out of a hat) you have to convert that to a percentage to find out if it is useful or not. 1 mpg gain for a 14 mpg car is roughly 7% better fuel economy. Not bad if you can make that work.
@@justinsane7128 I'm afraid I can't help you with your reading comprehension deficit. But if you google "Adult Literacy Classes" you might find some good resources.
That seat belt cover is like snuggling up with Chewbacca every time you drive. Thanks for doing this video. I am surprised too. I thought for sure you would get 1-2 mpg better. Can’t wait to hear how the long term testing does.
I think odometers work by counting wheel rotations. So, the larger tire would need less rotations to cover the same distance as the smaller tire. Making it appear to not go as far, and therefore appear to use more gas :)
Surprised me too, Joe. I know on my Tacoma, when I went to the larger KO 2's, I lost about1-1.5mpg. And that is going with the largest KO 2 I could put on the factory rims. I also added a 2: lift. Now I'm wondering if it is the lift that reduced the mpg, not the tires. I do know the truck is more sluggish with the KO 2's, but, it's a Tacoma. They are always sluggish.
@@chrisdevalcourt648 I did not. I have a Garmin Overlander that is always on and I use it for mph info. As far as mpg calculations, I just filled tank to the top of filler neck twice to check economy. Filling up to neck is not a good thing to do, but I did it anyway so I had the most accurate read on actual fuel consumption. That’s close enough for me. I really don’t normally concern myself with fuel mpg. I’m going to drive whatever I want to drive regardless of fuel consumption.
I have a Ford transit can with standard continental tires...and the big story here is GROUND CLEARANCE. We have been limited in our off road dispersed camping out west with such a poor ground clearance. Any improvement in ground clearance would make our big trips so much better.
Agreed - I had K02's (235/75/16) on my self built Transit for 7 years. The larger size help dispersed camping accessibility a bunch. BUT - I felt even that was limiting so this winter I had Agile Offroad install their lift kit (2" front 3" rear $$$) . That lift kit was a huge game changer on getting even further out there. (the ARB rear locker helped as well-:)
Small test loops cause big variances. The TFL channel guys do the same thing. It's hard to get the true numbers until you can average out a few tanks. Interested to see how it works out. Staying east of the Rockies will have a big impact on your pocketbook if that's what you are concerned about.
It depends on the application of the vehicle and if the mpg lost is worth it. I have had bigger tires on a vehicle - it not only cut down on mpg but it wore out the suspension quicker (even with the modifications done by a professional) and the tires cupped. My current truck was sent out from the factory off road ready.
I like the way you calculated taking into account the odometer calibration. I know that if you don't take that into account the mileage looks worse than it really is. With these vans, I bet the biggest thing affecting mileage is going to be the wind resistance of the van, then the weight, then the driving style, then the tires (diameter, weight and tread design).
I am surprised you didn't get a little better mileage. I have a Pleasureway Ontour 2.2 that is built on the larger Ford Transit with dual tires. On our recent trip of over 4,000 miles to Idaho and Montana from San Diego we averaged 16.1 mpg. On a shorter trip where I was either going up a mountain to 6,000 feet and back down I got 14.5 mpg with my odometer saying only 11.8 mpg at the highest point on the mountain. (I have solar panels on the roof, the A/C and two electric bikes on the back. I drive with full fresh water tank.)
I also have a pleasure ontour 2.2. We traveled 6 months this year and tried as many off road dispersed camping as we could and to me the big issue is GROUND CLEARANCE. These larger Storyteller wheels and ties will give VERY VALUABLE AND BADLY NEEDED CLEARANCE IMPROVEMENT IMPROVEMENT. I'll try shopping for them when the standard issue Continental tires wear out.
Interesting and different from my experience with over sized tires. I’d compute distance with a gps for accuracy and bump that highway speed up to 75. Unless ya really take it easy through Kansas ha! Those motors will roll at 90 effortlessly. Great test and anxious to see the “real world” results. Thanks!
This is a very good video and with good information. Tire size always makes a difference to a certain point. Too much over or under and the improvements go down. The real answer to this question is that it depends on how and where you drive. If you're doing a lot of accelerating during your drive then smaller tires are better as it takes less power to increase their speed. If you're travelling only on highways going across country larger tires are better as you can get more distance per power consumed. The reason for the results in the video is due to mixed travel. Stock tires are chosen by the company for mixed travel to accommodate all drivers. Larger tires are put on explorer vehicles for the extra ground clearance along with exploring generally means covering more distance.
I have a f150, for the second set, I bought Michelin LTX. 275-18-65. Great tire. $280 each. Forscan can get you programmed for tire size matching to the speedo
Sprinter T1N, short wheel base, 4x4, 2.7CDI(diesel), year 2000, 5-speed manual, 154hp: 26mpg or less with bigger 265/70/15 , 30mpg or less with 225/70/15, distance measured with GPS not with odometer
Thank you so much for making this video. I do like fat and bigger tires on my vehicles and I trully wanted to get a more scientific approach on the gas mileage. Best regards!!
It occurs to me that if you’re relying on when the pump automatically shuts off, that wouldn’t give you an accurate indication of the level of gas in the fuel filler pipe neck. Even the same pump will shut off at different times. Although we’re often told by “the experts” (whoever they are) not to add more fuel after the pump shuts off, my experience with several different vehicles has been that I can often add as much as 2 gallons of gas one time and as little as half a gallon the next time, from the same pump-they’re just not that accurate. So noting the level of the fuel in the filler pipe neck would be the only way to be accurate, I think.
You are correct Cary. I can easily put 2-3 more gallons in the truck if I take the time to fill all the way up. So if you’re going to look at actual fuel used, that is the only accurate route to go.
Indeed not accurate enough. Pumps shut off differently even under identical conditions! Longer trips (miles) would give better results. Wind is certainly a factor as well as load and driver techniques and speed. Even more variables than that. Some kind of computerized testing taking into account all variables would be most accurate. Don't think it would be worth it!
Side note question: where did/do the factory tires come from? Four tires would be too bulky to carry around in an rv regularly; and I doubt you would buy 4 tires/wheels just to test potential mpg differences.
Basic math. The taller tire has made your gear ratio a highway ratio in the name of ground clearance so its harder on the engine. (think of a 10 speed bike that works the easiest in 4th gear aka factory tire circumference ...the bigger tires make it pedal and work like its in 5th gear all the time instead of 4th) The smaller tire keeps the engine at factory set specs for rear end ratio and living in the engines power band....of course air pressure and width will also have an effect. Bottom line is that you get better off road clearance with the taller tires but better response and power especially fully loaded or towing up hills with the factory smaller tires. Your choice. So fully load up with groceries and water and toys and maybe even a small trailer with a motorcycle and run the test again and you will see the smaller tires shine...especially going uphills.
Surprised there wasn't more impact. I wonder if in more city driving you wouldn't see a larger impact from the bigger wheels. Theory would be that larger radius wheels is effectively changing the gearing on the vehicle, it would then require more low end torque from the engine to get them spinning
Does the 10-speed transmission use speed to make shift decisions? I think that unlikely. It likely uses rpm and load. If so, then different diameter wheels will have only a small impact on mpg. Basically, the difference would show in 1st gear and in 10th. But in all the other gears, the transmission shift points should adjust to accommodate the different wheel size.
With a big tire you'll get better gas mileage on a very flat surface. But that same tire on hills a mountains actually will stress the suspension but mostly the drive train.
Would be interesting to see a video explaining The rationale of switching back to a van and how that compares with the reasoning from before with the switch from the van to a truck camper.
Really enjoyed the video, especially when you pointed out you used a google map of 45 miles. The odometer would change actual miles per tire. I got a new RAM and the dealer put on a front level and firestone destination 35 12.5 r20, and the truck should have 275/55 r20. They look great, smooth enough, not calibrated so mph, mpg, speedometer shows 40 and gps 44, gears change at speed so are off, and warranty of 70,000 miles is being eaten away faster. Im heading back to the dealer to get the original tires on, even though they will be much cheaper.
If you account for air drag, rolling resistance, pavement temperature and any other variables that could affect the outcome, both tires give the same fuel efficiency.
This was a great test, Joe! So much work to change out the tires! You are so handy, wow. I think this test was very useful to every single RV owner. We all wonder if tires make a big difference and as you showed, the larger ones are minimally higher but way more functional. I wonder if the tires count as RV max weight limit or are exempt? The bigger tires certainly carry more load. That is great. Nice to see you both again! Hi Kait!
there's a lot of research into this with regard to cycling. the main factors involved in addition to solely distance per revolution are rolling resistance and rotational mass. the more rolling resistance and rotational mass, the harder the engine needs to work to complete one revolution. likewise, a larger tire radius means more distance traveled per revolution. if you can reduce the rolling resistance and rotational mass, you should gain MPG, but to beat the previous wheels, it would have to equal or better the rotational mass and rolling resistance of the smaller wheel while maintaining the larger tire radius. doing this would sacrifice some grip in the winter though
yes and tread pattern....from lots of experience . 1 car i went from MT to AT and saved 7 mpg , i put slightly oversize AT on a van and lost 5 mpg ( maybe the efficiency of the particular vehicle makes a difference smaller engine may have to work harder ? )
I get 18 on my 21 transit with the Ecoboost (14k miles on it). I've seen as low as 14 with a nasty headwind, and we don't have a lift. The reduced weight of the storyteller wheels could also have an effect?
@@Weretherussos Oh that’s good to know! I haven’t taken the time to weigh mine. Probably going to swap them for the owl van wheels when the stock tires go. We don’t do any crazy wheeling beyond a gravel road here and there so not doing the lift or crazy big tires. It’s strange to me that your mileage is so much lower than mine.
Have you made an odometer reading comparison? Is one mile on the odometer the same on each set of tires? Find a mile marker, go 10 miles and compare the odometer with both sets of wheels. I might suspect the the ratio will be different. If so then you would need to apply that ratio to your odometer reading for each set of tires before calculating MPG.
Wow your MPG makes my eyes water. We have a 3½ ton automatic Transit camper with a deisel engine. Last year we went on a 6500 round trip from England up through to the top of Norway and back on the factory fitted Michelin Agilis. Only about 1500 miles on motorways the rest on twisty bendy and hilly roads. Our average MPG when we got home was just over 27MPG.
Don’t forget that your mpg converted to US would be about 22.5. Still much better but our van is the AWD 4.5 ton model that’s lifted, with the roof rack, side ladder etc which really reduces fuel economy.
The weight is the problem mainly. The size of the tire is less than 5% of the MPG (30 inch vs 28 inch). What is the total weight added after the completed build? if you can cut down the weight, it will help a lot more than just the tire. Most of the van build videos on youtube are building it like a tank.
I don't know if it has been said, but there is going to be a noticeable difference in engine RPM at the same speed with the different size tires. Once you correct for the change in odometer it very well could be that the gap between the two tires gets smaller the longer you ride at speed. This effect will be countered by the additional torque needed to accelerate however so it wouldn't surprise me to see a widening difference of "city" mileage. I had a 4cyl Jeep Wrangler when I was a teenager and when I put on 33" tires it actually increased my MPG due to this effect. I have a MODE LT as well and I can tell however that the worst hit to MPG is the roof deck and ladder... Plus.... the BFGs just look too dang good to take off...haha
Around town the smaller diameter tires should be better because of the starting and getting to higher rpm sooner. The larger diameter tires will do much better on the highway because of the lower rpm that he mentioned. I don't know the torque curve for the 3.5 ecoboost but generally speaking there is lower engine friction at lower rpm. The larger diameter tires are equivalent to going to a lower numerical axle ratio which helps mileage.
there will be a greater difference going from 33s to 37s on your f250 IMO compared to their experience of going 28s to 30s. Shouldnt have any functional problems on your truck, but the difference between 33s and 37s is pretty significant, so I would expect to see a less mpg.
So I did this with my F150, trading the stock P rated car tires for BFG KO2s (both same size, but 33"). I encountered some differences, but I have a hybrid and the increased wheel weight reduces time spent in electric mode which has an outsized effect on my mileage. Nonetheless, my highway experience is relevant to yours. I found that adding tow mirrors dropped my mileage by a full MPG (Aptera, the EV company, states that their CAR's cD is lower than Ford's tow mirrors alone). I paid Ford $750 for the privilege of adding that much drag to my truck, and I'm going to keep them because the blind spots in the truck are awful, but stock mirrors actually make a difference. Your van may be the one vehicle with MORE drag that my truck (even then it's iffy because your front profile is far more aerodynamic even if the vehicle is overall taller), thus we both have to contend with drag the the single greatest determinant of mileage at highway speeds. The three things that have helped that the most are, in order of descending importance, 1) slow down to 62 or so MPH 2) follow a truck (automated cruise control helps a ton with this- there is a notable benefit even the nearest automatic follow distance) and 3) utilize favorable wind. 1 and 2 often go hand in hand, as most big trucks have been slowed by high diesel prices, so you wind up going 62-65 MPH and drafting as a package deal. 3 is very often a "luck of the draw" phenomenon for me, but you guys may have more freedom to choose destinations, routes, and travel times: don't discount the wind if you're in the plains or out west. My mileage varies a ton. My record was 32 MPG in 45-50 MPH heavy traffic north of San Antonio over about 50 miles on interstates during rush hour. My highway record was 28 MPG which depended upon a tailwind and following an 18 wheeler at ~64 MPH. Even with the heavier tires and tow mirrors, I can get 25 MPG behind a big truck at 64 MPH. In stark contrast, I can get 16 MPG if I go 75 MPH with no truck ahead of me (and both of those numbers from from essentially still air). That equates to a 150% increase in range just based on driving habits, with a 20% increase in travel time. While you guys don't need to worry about trying to get into electric mode, your drag is so severe that you might benefit more from these techniques than I do. Happy trails!
@@chrisdevalcourt648 I think that it's important to clarify what you mean by "drafting". Following another car at 10' at highway speeds isn't the same thing as following a big truck at 100'. I think that the question you're getting at is: "Can you follow a truck at a distance which permits an emergency stop but which also provides aerodynamic benefits to the folllowing vehicle?" My limited data says "yes."
@@amschind good point. The size of the vehicle you are drafting, its speed as well as your speed make a difference. I'm not sure at what distance wind tunnel testing has shown to be effective.? Years ago we used to draft the big 18 wheelers with a VW bug. Had to get dangerously close. Of course when you are young and dumb like we were, you do dumb things like that.!
That roof rack is what is killing your mileage. My van (3.5 eco high extended, 8500lbs) gets 17mpg and I mangaged 19 mpg for a baja trip (mostly doing 55).
Does storyteller not match the speedo to the tire size they sell with it?! Seems like an issue for that kind of money. Also how did you get the factory wheels and tires?
A tire with a thicker sidewall like an All Terrain would have is going to be stronger or able to take more of a beating is also why a tire with 6.5-7in side wall also gonna help to not damage the rim/wheel. And all being good for overlanding/rock/dirt rds. Based on number of plys and load index/ratings too.
What is the cost difference between the 4 big tires and rims , compared to the 4 factory tires and rims ? Do you carry a spare tire ? Is it a big tire or factory tire . If you blowout a tire while out on a trip , which tire will be easier to locate and replace ?
That larger tire is like a lower gear using less rpm's. On a relatively flat drive it should help. You'd think a lot of starting and stopping and chill climbing the increased unsprung weight may make more of a difference, that's my hypothesis anyway lol
Thank you for this video. I also have Ford Transit 350 without ecoboost. I want to get the larger tires but I worried about the gas mileage and the noise. With the factory tires and rims I am getting 13.9 to 14.2 MPG. I wonder if the lift makes a difference?
Forgive me if my question was answered somewhere else, however: I was under the assumption that the vehicle’s computer had to be programmed as to what size tires were in use, primarily why it is recommended to stay with the same size and in some cases tread pattern when buying new tires (suspension and handling is also at play here too). This is due to differences in fuel mapping in/at the engine. Still, why you saw little difference between factory and aftermarket, especially with such a big difference in size, is very interesting! I also assume that the aftermarket conversion took this into account?
The largest issue when putting bigger tires on is the gear ratio. This has 3.73 gears so larger tires don't affect it as much as a 3.23 gear ratio. The computer does not have to be reprogrammed but it is optimal to do so. That said, it's not as easy as just updating a setting. Ford is not able to update the computer for a larger tire like these so you'd have to do something aftermarket and that can be an issue if there is a warranty claim. If we saw a big variance in MPG, then I would say the engine's fuel mapping is way off for larger tires but here I think it's still pretty spot on. Just have to calculate the difference for speed and MPG since the speedo and odometer are off.
@@Weretherussos here in Tennessee, I’m originally from NJ, we have a metered mile. I assume it’s for calibration purposes (for radar, duallies with monster truck tires, etc. ? I’ve seen it all down here).
Great Job Joe! Yes, I would have thought the tires made more of a difference. Very interesting video. Looking forward to seeing the trip to Alabama! Also nice cameo clip of Kait!
It is impossible to account for effect of the wind/air resistance in the real outdoors. When towing against the wind vs with the wind our mpgs vary from as little as 9.5 mpgs and as much as 12 mpgs (towing a trailer so yes a huge front area but still similar 20% effect can be a factor for the van) over flat Saskatchewan/Manitoba roads. Higher profile of the van (on larger diameter tires will also play a factor but that would go to support the factory tires as more fuel efficient in this experiment. I'm looking forward to the long term results :).
I too have the Storyteller Mode LT. It came with 21 gal of water, we drove it home and got 9.9 mpg mostly freeway and highway. Sandy OR to Astoria OR. We were disappointed to say the least. Were your water tanks full, half full? Weight makes a difference. Hopefully it gets better.
I really appreciate the work you have put into doing this. I drive a Jeep and put the factory size while being more off road aggressive, so this will give me a point of reference. Thumb up for this.
hmm not sure you can improve much on the overall platform, because I would say wind resistance and drag is a biggest overall factor. The factory continentals are crap in the snow up here in Canada I know i get stuck on wet grass, forget certain snow conditions. I am in the market for new tires, i do not drive on gravel much even here in Northern Ontario. However i have a huge solar panel on the roof that i would like to streamline.
What are the respective tire sizes? I'm not planning on doing much offroading will swap to less aggressive tires like Michelin Defenders on the LT I'm getting.
I agree with other sentiments that is surprising. I know with my old 2003 TDI wagon, I would see a 2-3 MPG drop when I switched from OEM size winter tires (195/65-15) to my larger and slightly heavier summer tires (205/50-16).
Having a campervan that came with KO2s when I bought it, I have wondered about this. KO2s are great, but at what cost. It will be interesting to see what your long term experiences with each are.
Sorry, this is going to sound really dumb, please be kind. As the aftermarket tires have a larger diameter how does the van/computer know how fast - or far - you are going as the wheel revolutions will be different over the same distance as the original tires. yes, I am clueless, I would love to know the answer. Great video, thanks for sharing
it is really a give-and-take situation. if you're rolling down a straight flat highway with constant velocity, your big tires will really shine. the bigger tires will cause the engine to work less to keep the same speed. however with each acceleration (stops and starts) it's gonna cut into that advantage greatly. also steeper grade hills will kill any advantage of the big tires.
I wonder about the factory gear ratio. It probably was not expected to be a RV. There used to be after market w/ overdrive final drive gear ratio. They were expensive though. Another option would be to add electric motors for accel assist and regen on hills.
Well, that was a surprise! I'm now getting 13.3 driving conservatively, which is all I expected. I can imagine interstate driving at +70mph would drop the mileage significantly. Thanks for doing this for us LT'ers, Kait and Joe. Very nicely done.
I have a 2020 high roof withe the non turbo 3.5. On a run from NY to Florida at 65mph i got about 14 mpg on two tanks. So i tried 75-80mph…was the same mileage. The ten speed doesn’t seem to care to much. On the highway maybe hiding behind a tractor trailer would do better. I also get 14 driving locally. Its not a camper but probably carries 750-1000 pounds of tools daily. So no matter what kind of driving i do it seems to get the same milage, but i don’t have a lead foot. I typically dont drive more than 40 miles a day so the gas engine was my choice. Most new diesels are problematic and cost more up front. I loved my old diesel truck but it didnt have DEF and the associated problems.
Nice video! I just received my Ford Transit Switchback and I'm trying to figure out if the Continental tires are good enough for the weight of the build out now. Also, what PSI should it be running on? Thanks for your feedback.
Good comparison. Thank you. We have a 2022 Transit AWD, HR, 3.5 Eco, currently with the stock tires, but interested in going to a larger size. So far we're averaging around 16 mpg's. We have a roof rack with a couple solar panels and a Maxxair fan on top. Still building out the inside. Naturally, we'd like to have better, but I'm happy with 16. What kind of air pressure are you using in your stock tires?
Do you have a spare KO2? Where do you carry it since, as I understand it, the KO2 won't fit underneath. Any ideas on how I can convert the spare tire area to storage?
Usually putting a taller, but more aggressive tire doesn't really affect MPG's. The all terrains are wider and more aggressive, so they're less efficient, but the taller tire takes you further per tire rotation. So one spin on the taller tire and you go further, but you lose acceleration. You really should reprogram your speedometer so the mileage and computer MPG's are more accurate. The BFG AT's look great!
Nice to have you do this comparison. I suspect there can be quite high variability in pump shut-off, especially with a few gallon test. Good to follow-up with a long distance test. I wonder if you can share more on the likes/dislikes of a 4x4 B-class over the 4x4 truck camper. I imagine comfort, overall room, parking, driving and access while driving are big factors. Off-road capability may be similar? Your ranking of these would be interesting.
Get the tiresizer app, it will tell you exactly how many turns per mile each tire needs. Example: If the big tire would show 10% less revs per mile and show 3% more gallons per distance, that would mean it makes 7% better MPG with the big tire.
i drive an f150 with the coyote engine, about 900 pounds of aftermarket stuff (winch, bumpers, crane, camper top) i need for work. i replaced the stock firestones with 33" ko2's inflated to 50 psi because i kept puncturing the sidewalls of the firestones when driving out in the paddock. you people all hate me because on the freeway im the guy doing 45-50 mph in the right lane.
if i never leave the farm, my mileage is 16.5 give or take .2 mpg. if i spend half my time on the freeway, 17.2 ish. if i spend a whole tank on the freeway 18.5.
towing a trailer of any weight drops it back to 17.2ish.
if you want to save fuel, you'd be better served to simply drive slower. it saves a lot of money and costs you a little time but its up to you which is more important.
To save a lot of gaz... slowdown on the highway. 57 to 60 max. It will help a lot !
The larger tyres will up your gear ratio, it will slow down your acceleration and use more fuel to do that but once your up to speed you will use less fuel, the lower RPM is the confirmation of this.
The KO's are the best compromise for on/off road and last a very long time so they save you money there
KO's "last a very long time"?
Well I had the KO1's factory installed on my 2013 Ford Raptor. Not abusing it, not hauling anything and not doing stupid TH-cam Raptor showoffs stuff - mainly driving on normal roads, rarely dirt roads. And the KO1's did not pass inspection after only 19K miles. Now I have the KO2's and have about 11K miles on them. Will see how long they will last. I doubt they will do better than the predecessors.
FYI: The KO's do NOT last a very long time for sure - believe me - and I am very disappointed as I was expecting at least 27-30K on them.
The vehicle is engineered to work best as it come out of the factory line - change the tire diameter and you will be messing up the speedometer which in turn will affect transmission gear up/down points and also mess with torque tolerances on transmission/axes - you might gain a few miles per gallon on FLAT terrain and lose on hills as it will be needing more HP than before do to larger tires.
@@gt-c- I think one’s driving habits affect tire wear. I have the e-rated KO2’s on the Tacoma and keep 45lbs of air in them unless I’m off-road. But, unlike your truck, my Tacoma doesn’t have the get up and go your truck has. And, I could careless how many seconds it takes me to get up to 60mph. I go easy on the gas and easy on the brakes. I don’t drive fast, only about 62-65 on interstate. I still have original rear brakes and replaced the front pads at 120k just because I thought I ought to. They still had life left in them. I expect to get at least 60k out of this set of tires as well. I’ve got 30,000 on them now and they still look great.
@@jimandvalstravelchannel Thank you for the feedback. In addition to what I already mentioned above: I do not abuses this truck, do not break hard, do not do donots, do not drive aggressive, do not go above 70-75 mph and do not burn rubber. It is a big truck (a tank) I agree, almost twice the weight of a Tacoma, but still considering all of these conditions,,,the KO's should have lasted more.
Bingo: the lower engine RPM washes out the tread inefficiencies of the larger tire. I'm glad you did this test.
Same here
There is definitely a lot of things acting for and against better MPG here. Taller tires, on nothing but highway use, will get you better gas mileage, but they have to be the same or even narrower tire size. Rolling resistance is what’s offsetting the gains you get with the larger diameter tire. Especially when going to a more aggressive non-highway tread. Once you start to do quite a bit of city driving, especially stop and go, this is where you lose drastically with a taller tire. So if you did more, or more aggressive city driving, and less time on the highway, you’re going to see a lot worse gas mileage. Although, if you have a trip planned, that’s gonna take you 90% on the highway, the taller (and not overly wide with highway tread) tire will definitely be best. Not just for fuel economy, but for other factors as well.. if the tire is an aggressive tire, it will be just like what they experience with their test.
Maybe in the future, we will have tires that expand from the center of the tire while decreasing the tire width tremendously to reduce rolling resistance. Then go back down to smaller diameter tires for city Drive.
Or we ditched Tires all together and just disco with flying cars.
You can use an OBD tool to see actual real time fuel economy. The tool and associated software can see how much fuel is going through the injectors. The Everlanders use a similar device but I can't remember the brand
Awesome video, have the same van but the NA engine and consistently get about 18 mpg. Was wondering how the larger tires would affect it so now i know. In my opinion whats killing your mpg is that roof rack acting like a parachute. Keep up the interesting and informative videos! 👍
How was the ride? That would be an interesting comparison. Quite a challenge to set up criteria. I would think that a narrower tire would get better gas milage considering less friction and resistance.
It's my understanding that a full build-out on any of the high-roof vans will only result in about 13-15 mpg.
Yeah, you're pushing 9,000 lbs around, so it's not surprising. I'm wondering how much weight could really be saved by using light materials, honeycomb panes, etc.
Okay, maybe my van doesn’t count as “full build out” I don’t have a bathroom or shower. And I don’t store 100 liters of water. BUT my 2019 sprinter LWB gets 18 to 21.
@@AdventureOtaku Full build out on a 148 Chassis, will likely be in the 9-10 K lb range.
3 factors (minor) that you didn’t mention are tire and wheel weight, width, and the fact that the aftermarket wheels lift the van creating slightly more wind resistance. I have an Escape with 2.0 eco boost with a small lift and upsized Wranglers and the biggest difference is IN MY HEAD as the display shows average mpg about 10% lower than it used to. Of course I didn’t recalibrate Speedo so makes perfect sense. I also notice a little wind noise from under the front end now and suspect the air under the car is more turbulent.
Two thoughts 💭
1. Wind! By any chance, do you know if wind changed? Even 5mph tailwind change into headwind is enough to cause a 2mpg increase for me.
2. Lower RPM! Like you mentioned it change from 1700 to 1900. Could slightly affect your mpg too; although not as much as I would expect from headwind/tail wind.
What is the weight difference between those wheel/tire sets? This could greatly affect your mpg. Once the heavy tires are rolling, extra weight requires less energy to keep it moving. But heavier tires take more to get them going. 45 miles is a good start but your 1/4 gal diff would be a full gallon at 200 miles and depending on tank size and normal miles per tank, you could be at 1.5 gallon diff per tank
The Ford 3.5L Eco-boost is notorious for gas guzzling when you drive the twin turbos… And acceleration or in towing. You can help that by avoiding a “lead-foot”!
Great analysis! Awesome van! We have same van (not nearly as cool) and we did notice a loss of MPG at speeds over 65 MPH and it progressively gets worse as you approach 80 mph (we went from Vanco stock 255 75 16) . Our van is a medium roof, but the tires gaves us almost 1.5" lift as it now barely fits in our garage. When our van tires were brand new our speedometer was off by 5 miles (6 at over 67 mph according to GPS). Our van is a 2017 and we get an average of 15/16 mixed city/hwy. We keep our speeds under 65 MPH and try to stay around 50 MPH on lonely roads and we can get up to 19 MPG (I GPS from gas station to gas station and use the miles driven/gallons pumped). Thanks again!!!!
From your video a month ago, you were getting 12mpg. Now you are improved to 14+mpg. Soon, it’ll be 15, 16, and 17mpg. As my Transit Ecoboost engine broke in, exact same numbers. There seemed to be a more pronounced increase after the first oil change. Likely the break-in oil from the factory is thicker. I still have pretty low mileage on my van, but I just got over 17mpg on two consecutive round trips from Santa Cruz to the Sierra Nevada mountains and back (twice, to be redundant). Frankly, I was very concerned at 12mpg when I first got the van. At 16mpg, I felt relieved. Now at 17mpg, it’s not bad at all. (Makes me pleased I didn’t spend for the diesel Sprinter.) I’m not sure I’ll get to 18mpg or even 19mpg, but that would be fantastic!!! As you know, gasoline here in California is pretty expensive, and it hasn’t come down from the peak hardly at all (contrary to what the media is reporting about -$1 for the national average). Anyway, be patient and I expect you’ll be rewarded. BTW, I ordered my Transit with the 31 gallon tank, and that is a nice feature. The extra range makes it easier to buy gas at lower priced stations.
I actually just changed the oil about 1500 miles ago and it’s been getting better - however we also took the motorcycle off the back and removed the running boards so we lost some air drag plus about 500 lbs
@@Weretherussos Driving style also helps mileage. I tend to get higher mileage than my wife, for example. I always beat the EPA estimate on every car. I get off the gas pedal sooner and coast. Drive like you are trying to avoid using the brake pedal. I don’t accelerate super fast or super slow - just normal. But I keep a reasonable following distance and look farther up the road for red lights, slow-downs, etc., thereby using the brakes less often. Gas has energy. You put the energy into motion. Your vehicle’s motion has potential energy. Then you brake and throw away all that energy by converting it to heat in your pads and rotors, which dissipates to the air (causing global warming, LOL). By using your brakes less, you are being environmentally conscientious. The result is manifested when you buy slightly less gas. The other way to think about it is don’t put more gas into your engine (via the pedal) than you need.
@@Weretherussos To reduce air drag, I put expensive CIGS flexible solar panels on my van’s roof. Unfortunately, they have delaminated, so I bought a rack and some glass panels. The rack is low profile and comes with a faring, so hopefully it won’t hurt mileage too much. We’ll see after I install it.
What octane fuel are you using?
@@noahklein360 87 from Costco. Cheapest here in California.
Very interesting and I look forward to the next installment. There are 2 other questions I hope you answer. 1) how does each set of tire differ in handling, and road noise; interstate, 2 lane highway and off highway driving. I’ve been debating for a while if I want a more aggressive tire. I assume there is a lift on your van, was there any sheet metal removal in order to accommodate the larger tires?
Answer is already available by looking at electric cars that offer multiple tire sizes. Ranges are lowered with the larger tires. It’s all the same physics regardless of whether your fuel is electrons or petrol. This is only true within a reasonable range - get too tiny on the wheel size and other problems occur.
Because the reduced final drive ratio with bigger tires (lower numerical ratio) the engine also has to work harder on acceleration.
Excellent. If most of your camper van driving is across country on interstate highways, the larger diameter tires should give much better mileage.
It does change the drag coefficient and yes it does affect gas mileage. Says Tesla and Aptera who both have done extensive testing. However you don’t wish to get stuck so It may be worth it depending on how rough the places you go.
I think you experimental design was right on (same pump, exact same route at the same speeds). Your comparison numbers are what I would expect based on similar comparisons made over the years in my vehicles. I would expect larger wheels with the same tread design to be equal. And I suspect that the lower MPG for your KO2s might be a result of the more open tread pattern and higher rolling resistance. (There are alot of us Dave Johnsons ;-))
I suspect that tire size is going to have a fairly limited effect on your fuel economy.
Larger tires require more torque to turn to provide acceleration and maintain speed against wind resistance. Since your transmission has not changed (and the engineers have engineered your car for a specific tire size) you will consume more fuel to achieve the same acceleration and fight any forces that are trying to slow down the car (wind resistance, road friction, gravity). This is a net negative.
But, larger tires will run the engine at a lower rpm on the freeway. This is a net positive.
Finally, having an aggressive tread will result in more of your fuel being turned into tire heat vs. forward motion. Once again, a net negative.
These might cancel each other out depending on your driving style and where you are going.
But... all of that is probably swamped by wind resistance.
With a large, fairly un-aerodynamic shape, most of your fuel is burned fighting the wind. When that is the case, the slight difference that you would experience from the bigger or smaller tires would become a tiny fraction of the overall fuel consumption.
Consider an extremely efficient car (like, say, an Aptera). Since this car is very aerodynamic, a smaller percentage of its fuel consumption is used to fight wind resistance. That means any factors that affect OTHER aspects of its fuel consumption (like road friction or acceleration or fighting gravity) will have a proportionally larger affect on its overall efficiency. So tires might actually change these numbers a fair bit.
Since a van is essentially a giant brick trying to move through the air, a much larger percentage of its energy is used up fighting wind resistance (which goes up as the square of speed, so doubling your speed will result in a 4x increase in resistance). That means the percentage that is used in ways that your tires have an effect on (acceleration, rolling resistance, etc.) will have less of a proportional effect.
BUT...
One other thing to keep in mind is that the way we think about fuel economy in North America is kind of backwards. We think of it in terms of miles per gallon, which hides proper comparisons behind a non-intuitive way of looking at the numbers.
Say you have a truck that gets 10 mpg and a car that gets 90 mpg. If you had the option of replacing the truck with another truck that gets 20 mpg OR replacing the car with another car that gets 100 mpg... you should replace the truck, even though both vehicles are improving on their predecessor by 10 mpg.
The reason is if you replace the truck, you will use 50% less fuel (for the same distance travelled). If you replace the car, you will only use 10% less fuel. You have to think of it in terms of percentages, not in terms of mpg improvements.
So IF you find out that smaller tires actually DO improve your mileage by 1 mpg (just to pull a number out of a hat) you have to convert that to a percentage to find out if it is useful or not. 1 mpg gain for a 14 mpg car is roughly 7% better fuel economy. Not bad if you can make that work.
Good points!
I didn't read all your dribble why don't they put 14 inch tires on semis then?
@@justinsane7128 I'm afraid I can't help you with your reading comprehension deficit. But if you google "Adult Literacy Classes" you might find some good resources.
@@justinsane7128 Pot holes?
That seat belt cover is like snuggling up with Chewbacca every time you drive.
Thanks for doing this video. I am surprised too. I thought for sure you would get 1-2 mpg better.
Can’t wait to hear how the long term testing does.
I think odometers work by counting wheel rotations. So, the larger tire would need less rotations to cover the same distance as the smaller tire. Making it appear to not go as far, and therefore appear to use more gas :)
They do but that’s why we were using GPS for speed and distance so that the “error” in the speedo was not a factor
@@Weretherussos Ha ! Now you got me thinking that we take GPS accuracy for granted, when includes me too. I wonder what the =/- accuracy really is ?
Surprised me too, Joe. I know on my Tacoma, when I went to the larger KO 2's, I lost about1-1.5mpg. And that is going with the largest KO 2 I could put on the factory rims. I also added a 2: lift. Now I'm wondering if it is the lift that reduced the mpg, not the tires. I do know the truck is more sluggish with the KO 2's, but, it's a Tacoma. They are always sluggish.
Yeah the lift is really going to make a difference.
Did you account for the taller tire affecting your speedometer reading?
@@chrisdevalcourt648 I did not. I have a Garmin Overlander that is always on and I use it for mph info. As far as mpg calculations, I just filled tank to the top of filler neck twice to check economy. Filling up to neck is not a good thing to do, but I did it anyway so I had the most accurate read on actual fuel consumption. That’s close enough for me. I really don’t normally concern myself with fuel mpg. I’m going to drive whatever I want to drive regardless of fuel consumption.
I have a Ford transit can with standard continental tires...and the big story here is GROUND CLEARANCE. We have been limited in our off road dispersed camping out west with such a poor ground clearance. Any improvement in ground clearance would make our big trips so much better.
Agreed - I had K02's (235/75/16) on my self built Transit for 7 years. The larger size help dispersed camping accessibility a bunch.
BUT - I felt even that was limiting so this winter I had Agile Offroad install their lift kit (2" front 3" rear $$$) . That lift kit was a huge game changer on getting even further out there. (the ARB rear locker helped as well-:)
Small test loops cause big variances. The TFL channel guys do the same thing. It's hard to get the true numbers until you can average out a few tanks. Interested to see how it works out. Staying east of the Rockies will have a big impact on your pocketbook if that's what you are concerned about.
It depends on the application of the vehicle and if the mpg lost is worth it. I have had bigger tires on a vehicle - it not only cut down on mpg but it wore out the suspension quicker (even with the modifications done by a professional) and the tires cupped. My current truck was sent out from the factory off road ready.
I like the way you calculated taking into account the odometer calibration. I know that if you don't take that into account the mileage looks worse than it really is. With these vans, I bet the biggest thing affecting mileage is going to be the wind resistance of the van, then the weight, then the driving style, then the tires (diameter, weight and tread design).
Yep you’ve got it right
I am surprised you didn't get a little better mileage. I have a Pleasureway Ontour 2.2 that is built on the larger Ford Transit with dual tires. On our recent trip of over 4,000 miles to Idaho and Montana from San Diego we averaged 16.1 mpg. On a shorter trip where I was either going up a mountain to 6,000 feet and back down I got 14.5 mpg with my odometer saying only 11.8 mpg at the highest point on the mountain. (I have solar panels on the roof, the A/C and two electric bikes on the back. I drive with full fresh water tank.)
I also have a pleasure ontour 2.2.
We traveled 6 months this year and tried as many off road dispersed camping as we could and to me the big issue is GROUND CLEARANCE. These larger Storyteller wheels and ties will give VERY VALUABLE AND BADLY NEEDED CLEARANCE IMPROVEMENT IMPROVEMENT.
I'll try shopping for them when the standard issue Continental tires wear out.
Interesting and different from my experience with over sized tires. I’d compute distance with a gps for accuracy and bump that highway speed up to 75. Unless ya really take it easy through Kansas ha! Those motors will roll at 90 effortlessly. Great test and anxious to see the “real world” results. Thanks!
This is a very good video and with good information.
Tire size always makes a difference to a certain point. Too much over or under and the improvements go down.
The real answer to this question is that it depends on how and where you drive.
If you're doing a lot of accelerating during your drive then smaller tires are better as it takes less power to increase their speed.
If you're travelling only on highways going across country larger tires are better as you can get more distance per power consumed.
The reason for the results in the video is due to mixed travel. Stock tires are chosen by the company for mixed travel to accommodate all drivers.
Larger tires are put on explorer vehicles for the extra ground clearance along with exploring generally means covering more distance.
I have a f150, for the second set, I bought Michelin LTX. 275-18-65. Great tire. $280 each.
Forscan can get you programmed for tire size matching to the speedo
Sprinter T1N, short wheel base, 4x4, 2.7CDI(diesel), year 2000, 5-speed manual, 154hp: 26mpg or less with bigger 265/70/15 , 30mpg or less with 225/70/15, distance measured with GPS not with odometer
You will get some rolling resistance from the K02s versus stock.
Thank you so much for making this video. I do like fat and bigger tires on my vehicles and I trully wanted to get a more scientific approach on the gas mileage. Best regards!!
You’re welcome!
I noticed that with the factory tire fill up you had less illuminated orange lites ,, was the a c off..
It occurs to me that if you’re relying on when the pump automatically shuts off, that wouldn’t give you an accurate indication of the level of gas in the fuel filler pipe neck. Even the same pump will shut off at different times. Although we’re often told by “the experts” (whoever they are) not to add more fuel after the pump shuts off, my experience with several different vehicles has been that I can often add as much as 2 gallons of gas one time and as little as half a gallon the next time, from the same pump-they’re just not that accurate. So noting the level of the fuel in the filler pipe neck would be the only way to be accurate, I think.
You are correct Cary. I can easily put 2-3 more gallons in the truck if I take the time to fill all the way up. So if you’re going to look at actual fuel used, that is the only accurate route to go.
Indeed not accurate enough. Pumps shut off differently even under identical conditions! Longer trips (miles) would give better results. Wind is certainly a factor as well as load and driver techniques and speed. Even more variables than that. Some kind of computerized testing taking into account all variables would be most accurate. Don't think it would be worth it!
Side note question: where did/do the factory tires come from? Four tires would be too bulky to carry around in an rv regularly; and I doubt you would buy 4 tires/wheels just to test potential mpg differences.
Basic math. The taller tire has made your gear ratio a highway ratio in the name of ground clearance so its harder on the engine. (think of a 10 speed bike that works the easiest in 4th gear aka factory tire circumference ...the bigger tires make it pedal and work like its in 5th gear all the time instead of 4th) The smaller tire keeps the engine at factory set specs for rear end ratio and living in the engines power band....of course air pressure and width will also have an effect. Bottom line is that you get better off road clearance with the taller tires but better response and power especially fully loaded or towing up hills with the factory smaller tires. Your choice. So fully load up with groceries and water and toys and maybe even a small trailer with a motorcycle and run the test again and you will see the smaller tires shine...especially going uphills.
Surprised there wasn't more impact. I wonder if in more city driving you wouldn't see a larger impact from the bigger wheels. Theory would be that larger radius wheels is effectively changing the gearing on the vehicle, it would then require more low end torque from the engine to get them spinning
Probably but there was a lot of acceleration in the hills which should have evened things out between the two
Does the 10-speed transmission use speed to make shift decisions? I think that unlikely. It likely uses rpm and load. If so, then different diameter wheels will have only a small impact on mpg. Basically, the difference would show in 1st gear and in 10th. But in all the other gears, the transmission shift points should adjust to accommodate the different wheel size.
With a big tire you'll get better gas mileage on a very flat surface. But that same tire on hills a mountains actually will stress the suspension but mostly the drive train.
Would be interesting to see a video explaining
The rationale of switching back to a van and how that compares with the reasoning from before with the switch from the van to a truck camper.
Really enjoyed the video, especially when you pointed out you used a google map of 45 miles. The odometer would change actual miles per tire. I got a new RAM and the dealer put on a front level and firestone destination 35 12.5 r20, and the truck should have 275/55 r20. They look great, smooth enough, not calibrated so mph, mpg, speedometer shows 40 and gps 44, gears change at speed so are off, and warranty of 70,000 miles is being eaten away faster. Im heading back to the dealer to get the original tires on, even though they will be much cheaper.
If you account for air drag, rolling resistance, pavement temperature and any other variables that could affect the outcome, both tires give the same fuel efficiency.
You need to put a 5 litre tank on the bonnet hood to be exactly sure you've used the same amount .mike Scotland
Thank you for another awesome video guys! 😎🤙🏻🤙🏻
This was a great test, Joe! So much work to change out the tires! You are so handy, wow.
I think this test was very useful to every single RV owner. We all wonder if tires make a big difference and as you showed, the larger ones are minimally higher but way more functional. I wonder if the tires count as RV max weight limit or are exempt? The bigger tires certainly carry more load. That is great. Nice to see you both again! Hi Kait!
Thanks! They count towards the GVWR
there's a lot of research into this with regard to cycling. the main factors involved in addition to solely distance per revolution are rolling resistance and rotational mass. the more rolling resistance and rotational mass, the harder the engine needs to work to complete one revolution. likewise, a larger tire radius means more distance traveled per revolution. if you can reduce the rolling resistance and rotational mass, you should gain MPG, but to beat the previous wheels, it would have to equal or better the rotational mass and rolling resistance of the smaller wheel while maintaining the larger tire radius. doing this would sacrifice some grip in the winter though
yes and tread pattern....from lots of experience . 1 car i went from MT to AT and saved 7 mpg , i put slightly oversize AT on a van and lost 5 mpg ( maybe the efficiency of the particular vehicle makes a difference smaller engine may have to work harder ? )
I get 18 on my 21 transit with the Ecoboost (14k miles on it). I've seen as low as 14 with a nasty headwind, and we don't have a lift. The reduced weight of the storyteller wheels could also have an effect?
Stock wheels and tires
The wheels were only 2 pounds difference in weight
@@Weretherussos Oh that’s good to know! I haven’t taken the time to weigh mine. Probably going to swap them for the owl van wheels when the stock tires go. We don’t do any crazy wheeling beyond a gravel road here and there so not doing the lift or crazy big tires. It’s strange to me that your mileage is so much lower than mine.
Weight difference of wheel + tire and rolling resistance of the tire are also important.
Have you made an odometer reading comparison? Is one mile on the odometer the same on each set of tires? Find a mile marker, go 10 miles and compare the odometer with both sets of wheels. I might suspect the the ratio will be different. If so then you would need to apply that ratio to your odometer reading for each set of tires before calculating MPG.
I applied the ratio in the video all verified by gps
Wow your MPG makes my eyes water. We have a 3½ ton automatic Transit camper with a deisel engine. Last year we went on a 6500 round trip from England up through to the top of Norway and back on the factory fitted Michelin Agilis. Only about 1500 miles on motorways the rest on twisty bendy and hilly roads. Our average MPG when we got home was just over 27MPG.
Don’t forget that your mpg converted to US would be about 22.5. Still much better but our van is the AWD 4.5 ton model that’s lifted, with the roof rack, side ladder etc which really reduces fuel economy.
The weight is the problem mainly. The size of the tire is less than 5% of the MPG (30 inch vs 28 inch).
What is the total weight added after the completed build? if you can cut down the weight, it will help a lot more than just the tire.
Most of the van build videos on youtube are building it like a tank.
I don't know if it has been said, but there is going to be a noticeable difference in engine RPM at the same speed with the different size tires. Once you correct for the change in odometer it very well could be that the gap between the two tires gets smaller the longer you ride at speed. This effect will be countered by the additional torque needed to accelerate however so it wouldn't surprise me to see a widening difference of "city" mileage. I had a 4cyl Jeep Wrangler when I was a teenager and when I put on 33" tires it actually increased my MPG due to this effect.
I have a MODE LT as well and I can tell however that the worst hit to MPG is the roof deck and ladder... Plus.... the BFGs just look too dang good to take off...haha
Interesting bench study, looks like I won't have any problems switching my f250 from 33's to 37's. :)
Around town the smaller diameter tires should be better because of the starting and getting to higher rpm sooner. The larger diameter tires will do much better on the highway because of the lower rpm that he mentioned. I don't know the torque curve for the 3.5 ecoboost but generally speaking there is lower engine friction at lower rpm. The larger diameter tires are equivalent to going to a lower numerical axle ratio which helps mileage.
there will be a greater difference going from 33s to 37s on your f250 IMO compared to their experience of going 28s to 30s. Shouldnt have any functional problems on your truck, but the difference between 33s and 37s is pretty significant, so I would expect to see a less mpg.
So I did this with my F150, trading the stock P rated car tires for BFG KO2s (both same size, but 33"). I encountered some differences, but I have a hybrid and the increased wheel weight reduces time spent in electric mode which has an outsized effect on my mileage. Nonetheless, my highway experience is relevant to yours. I found that adding tow mirrors dropped my mileage by a full MPG (Aptera, the EV company, states that their CAR's cD is lower than Ford's tow mirrors alone). I paid Ford $750 for the privilege of adding that much drag to my truck, and I'm going to keep them because the blind spots in the truck are awful, but stock mirrors actually make a difference. Your van may be the one vehicle with MORE drag that my truck (even then it's iffy because your front profile is far more aerodynamic even if the vehicle is overall taller), thus we both have to contend with drag the the single greatest determinant of mileage at highway speeds. The three things that have helped that the most are, in order of descending importance, 1) slow down to 62 or so MPH 2) follow a truck (automated cruise control helps a ton with this- there is a notable benefit even the nearest automatic follow distance) and 3) utilize favorable wind. 1 and 2 often go hand in hand, as most big trucks have been slowed by high diesel prices, so you wind up going 62-65 MPH and drafting as a package deal. 3 is very often a "luck of the draw" phenomenon for me, but you guys may have more freedom to choose destinations, routes, and travel times: don't discount the wind if you're in the plains or out west.
My mileage varies a ton. My record was 32 MPG in 45-50 MPH heavy traffic north of San Antonio over about 50 miles on interstates during rush hour. My highway record was 28 MPG which depended upon a tailwind and following an 18 wheeler at ~64 MPH. Even with the heavier tires and tow mirrors, I can get 25 MPG behind a big truck at 64 MPH. In stark contrast, I can get 16 MPG if I go 75 MPH with no truck ahead of me (and both of those numbers from from essentially still air). That equates to a 150% increase in range just based on driving habits, with a 20% increase in travel time. While you guys don't need to worry about trying to get into electric mode, your drag is so severe that you might benefit more from these techniques than I do.
Happy trails!
Great tips and the biggest drain we’ve seen with MPG is driving in a strong cross wind
@@Weretherussos Right? It sometimes seems like a strong crosswind is worse than a headwind.
I don't recommend drafting especially the 18 wheelers.
You worry the other driver and it's so dangerous! And possibly illegal in areas.
@@chrisdevalcourt648 I think that it's important to clarify what you mean by "drafting". Following another car at 10' at highway speeds isn't the same thing as following a big truck at 100'. I think that the question you're getting at is: "Can you follow a truck at a distance which permits an emergency stop but which also provides aerodynamic benefits to the folllowing vehicle?" My limited data says "yes."
@@amschind good point. The size of the vehicle you are drafting, its speed as well as your speed make a difference.
I'm not sure at what distance wind tunnel testing has shown to be effective.?
Years ago we used to draft the big 18 wheelers with a VW bug. Had to get dangerously close. Of course when you are young and dumb like we were, you do dumb things like that.!
That roof rack is what is killing your mileage. My van (3.5 eco high extended, 8500lbs) gets 17mpg and I mangaged 19 mpg for a baja trip (mostly doing 55).
Agreed
I know a few years ago when I went from factory 4 tires on a 2004 E350 to 1 size larger More aggressive off road tires my mileage was destroyed.
Does storyteller not match the speedo to the tire size they sell with it?! Seems like an issue for that kind of money.
Also how did you get the factory wheels and tires?
Which tires do you think are safer in terms of blowouts and road hazards? I would prefer to make my decision based on that!
A tire with a thicker sidewall like an All Terrain would have is going to be stronger or able to take more of a beating is also why a tire with 6.5-7in side wall also gonna help to not damage the rim/wheel. And all being good for overlanding/rock/dirt rds. Based on number of plys and load index/ratings too.
What is the cost difference between the 4 big tires and rims , compared to the 4 factory tires and rims ?
Do you carry a spare tire ? Is it a big tire or factory tire .
If you blowout a tire while out on a trip , which tire will be easier to locate and replace ?
That larger tire is like a lower gear using less rpm's. On a relatively flat drive it should help. You'd think a lot of starting and stopping and chill climbing the increased unsprung weight may make more of a difference, that's my hypothesis anyway lol
Thank you for this video. I also have Ford Transit 350 without ecoboost. I want to get the larger tires but I worried about the gas mileage and the noise. With the factory tires and rims I am getting 13.9 to 14.2 MPG. I wonder if the lift makes a difference?
Andrey on TFL Truck added bigger tires to his f-150, and had no real significant mileage drop. He has said the Ecoboost is either eco or boost...
Good Content! What seats are those? I have had lower back issues and those look like they would be comfortable!
Thanks! Here is the video we made all about the seats th-cam.com/video/Or-_Df4N9Tk/w-d-xo.html
The ECU needs recalibration when you change to a different tire size.
Forgive me if my question was answered somewhere else, however: I was under the assumption that the vehicle’s computer had to be programmed as to what size tires were in use, primarily why it is recommended to stay with the same size and in some cases tread pattern when buying new tires (suspension and handling is also at play here too). This is due to differences in fuel mapping in/at the engine. Still, why you saw little difference between factory and aftermarket, especially with such a big difference in size, is very interesting! I also assume that the aftermarket conversion took this into account?
The largest issue when putting bigger tires on is the gear ratio. This has 3.73 gears so larger tires don't affect it as much as a 3.23 gear ratio. The computer does not have to be reprogrammed but it is optimal to do so. That said, it's not as easy as just updating a setting. Ford is not able to update the computer for a larger tire like these so you'd have to do something aftermarket and that can be an issue if there is a warranty claim. If we saw a big variance in MPG, then I would say the engine's fuel mapping is way off for larger tires but here I think it's still pretty spot on. Just have to calculate the difference for speed and MPG since the speedo and odometer are off.
@@Weretherussos here in Tennessee, I’m originally from NJ, we have a metered mile. I assume it’s for calibration purposes (for radar, duallies with monster truck tires, etc. ? I’ve seen it all down here).
Great Job Joe! Yes, I would have thought the tires made more of a difference. Very interesting video. Looking forward to seeing the trip to Alabama! Also nice cameo clip of Kait!
Thanks you two!
It is impossible to account for effect of the wind/air resistance in the real outdoors. When towing against the wind vs with the wind our mpgs vary from as little as 9.5 mpgs and as much as 12 mpgs (towing a trailer so yes a huge front area but still similar 20% effect can be a factor for the van) over flat Saskatchewan/Manitoba roads. Higher profile of the van (on larger diameter tires will also play a factor but that would go to support the factory tires as more fuel efficient in this experiment. I'm looking forward to the long term results :).
I too have the Storyteller Mode LT. It came with 21 gal of water, we drove it home and got 9.9 mpg mostly freeway and highway. Sandy OR to Astoria OR. We were disappointed to say the least. Were your water tanks full, half full? Weight makes a difference.
Hopefully it gets better.
I really appreciate the work you have put into doing this. I drive a Jeep and put the factory size while being more off road aggressive, so this will give me a point of reference.
Thumb up for this.
hmm not sure you can improve much on the overall platform, because I would say wind resistance and drag is a biggest overall factor. The factory continentals are crap in the snow up here in Canada I know i get stuck on wet grass, forget certain snow conditions. I am in the market for new tires, i do not drive on gravel much even here in Northern Ontario. However i have a huge solar panel on the roof that i would like to streamline.
What are the respective tire sizes?
I'm not planning on doing much offroading will swap to less aggressive tires like Michelin Defenders on the LT I'm getting.
I agree with other sentiments that is surprising. I know with my old 2003 TDI wagon, I would see a 2-3 MPG drop when I switched from OEM size winter tires (195/65-15) to my larger and slightly heavier summer tires (205/50-16).
Having a campervan that came with KO2s when I bought it, I have wondered about this. KO2s are great, but at what cost. It will be interesting to see what your long term experiences with each are.
Also depends on the camping gear load full water etc
Also ur coffee added I'm assuming 8 oz of ore weight to account for
looking forward to the results with the stock tires/wheels after your drive to Storyteller land. Thanks for the video!
Did they recalibrate the van's transmission shift points when they put bigger tires on? That can adversely affect mileage
My 2019 F350 with Pleasure Way camper van on the highway going 55 mph I can usually get 15.5 mpg
Sorry, this is going to sound really dumb, please be kind. As the aftermarket tires have a larger diameter how does the van/computer know how fast - or far - you are going as the wheel revolutions will be different over the same distance as the original tires.
yes, I am clueless, I would love to know the answer.
Great video, thanks for sharing
It doesn’t so we hand calculate the mileage.
it is really a give-and-take situation. if you're rolling down a straight flat highway with constant velocity, your big tires will really shine. the bigger tires will cause the engine to work less to keep the same speed. however with each acceleration (stops and starts) it's gonna cut into that advantage greatly. also steeper grade hills will kill any advantage of the big tires.
Thanks! What size tire are ko 255 70 16? Or 245 75 16? Thanks! Nice driver chair too
Did you weight the 2 tire/wheel combinations to see if there is a significant difference. Could be another factor.
Makes me appreciate our 2WD van, with its 18-20 mpg.
I wonder about the factory gear ratio.
It probably was not expected to be a RV.
There used to be after market w/ overdrive final drive gear ratio.
They were expensive though.
Another option would be to add electric motors for accel assist and regen on hills.
No matter what the tires are, those turbos on that Ecoboost loves to guzzle premium fuel especially when you mash that gas pedal.
Been watching you all for sometime, and appreciate the content. Thank you.
You’re welcome!
Well, that was a surprise! I'm now getting 13.3 driving conservatively, which is all I expected. I can imagine interstate driving at +70mph would drop the mileage significantly. Thanks for doing this for us LT'ers, Kait and Joe. Very nicely done.
You’re welcome!
What octane gas are you using?
@@noahklein360 85 or there abouts, ie generally the lowest available. I hear no pinging, and performance "seems" good.
I have a 2020 high roof withe the non turbo 3.5. On a run from NY to Florida at 65mph i got about 14 mpg on two tanks. So i tried 75-80mph…was the same mileage. The ten speed doesn’t seem to care to much. On the highway maybe hiding behind a tractor trailer would do better. I also get 14 driving locally. Its not a camper but probably carries 750-1000 pounds of tools daily. So no matter what kind of driving i do it seems to get the same milage, but i don’t have a lead foot. I typically dont drive more than 40 miles a day so the gas engine was my choice. Most new diesels are problematic and cost more up front. I loved my old diesel truck but it didnt have DEF and the associated problems.
Nice video! I just received my Ford Transit Switchback and I'm trying to figure out if the Continental tires are good enough for the weight of the build out now. Also, what PSI should it be running on?
Thanks for your feedback.
Run the tire psi recommended by ford in your manual and the load rating of your tires will also be in there and stamped on the tires themselves.
Good comparison. Thank you. We have a 2022 Transit AWD, HR, 3.5 Eco, currently with the stock tires, but interested in going to a larger size. So far we're averaging around 16 mpg's. We have a roof rack with a couple solar panels and a Maxxair fan on top. Still building out the inside. Naturally, we'd like to have better, but I'm happy with 16. What kind of air pressure are you using in your stock tires?
Hi, I was wondering what the model number was for your scheelmann captain's chairs? Thanks
Here is a video all about them: th-cam.com/video/Or-_Df4N9Tk/w-d-xo.html
@@Weretherussos thanks a lot.
Do you have a spare KO2? Where do you carry it since, as I understand it, the KO2 won't fit underneath. Any ideas on how I can convert the spare tire area to storage?
Usually putting a taller, but more aggressive tire doesn't really affect MPG's. The all terrains are wider and more aggressive, so they're less efficient, but the taller tire takes you further per tire rotation. So one spin on the taller tire and you go further, but you lose acceleration. You really should reprogram your speedometer so the mileage and computer MPG's are more accurate. The BFG AT's look great!
They can’t reprogram the new Fords. So I use the GPS figure to calculate the MPG
Nice to have you do this comparison. I suspect there can be quite high variability in pump shut-off, especially with a few gallon test. Good to follow-up with a long distance test.
I wonder if you can share more on the likes/dislikes of a 4x4 B-class over the 4x4 truck camper. I imagine comfort, overall room, parking, driving and access while driving are big factors. Off-road capability may be similar? Your ranking of these would be interesting.
My car came with 18in tire. Should i swap to a 15 inch tire? Get that mpg
I couldn't find your second video of your trip. How did the MPG look with more miles on the factory tires and wheels going to Birmingham?
Here you go! 1,000 Mile Update - Do Larger Tires Affect MPG?
th-cam.com/users/liveBNeyglABfPU?feature=share
Great tips, as always. Thanks Joe n Kait :)
Get the tiresizer app, it will tell you exactly how many turns per mile each tire needs. Example: If the big tire would show 10% less revs per mile and show 3% more gallons per distance, that would mean it makes 7% better MPG with the big tire.
Someone researching vans options, 14.3 mpg. I'll keep my diesel truck. Thank you for the real video.
I have seen some tests where premium usage in the Eco Boost engine results in 5% better mileage -suppose it depends on driving style
Correct but typically the price difference negates the gain in MPG