Just the fact that you can pull the carrier out and set it up on a table and not laying on the ground under your vehicle (unless you have a lift, or take the rear end out, etc) is very important to me.
As a 12 bolt owner, I do find dropping the whole rear a tad inconvenient. But so is trying to shim things in place [I don't have the luxury of a lift].
The much more available used and cheap Ford 8.8" is popular... Is the Ford 9 3/4" used in SUVs stronger than the 9"? Getting into cars from the curb side used to be the LAW! In old 1940's-50's shows, most people, even drivers, get in from the curb side and slide over...
I remember when you could go into the junkyard and get a 9 inch Ford rear axle for under a hundred bucks and you had choices in gear ratios and widths... Man I'm getting old!🤓
One thing about the Ford 9-inch that sticks with me to this day, it happened 25-30 years ago or more, it was a NASCAR race on TV that I was watching in real time. Bobbie Allison pulled into the pits, and something in the rear broke for some reason, it was a fluke. There was a yellow flag at the time and everybody pulled into the pits for tires and fuel. Something in Allisons 3rd member broke. The crew chief immediately sent one crew member to their transporter to get another 3rd member, and as he was gone, the rest of the crew jacked up the car, took off the tires, pulled out the axles, took off the 3rd member, then the man that was sent to get another 3rd member got back to the pits, they put in a whole new 3rd member, reassembled the axle, Allison got back on the track, and never lost a lap, because everybody was in for gas and tires. He was at the very rear of the same lap, but it was the same lap. If he'd been running anybody else's axle, they would have had to disassemble the center section with a spreader, and everything else involved with a Chevy 12-bolt or a Dana 44 or 60, and he would have been screwed. But because the Ford 3rd member was pre-assembled, it was easy(ier) to deal with. He didn't win the race, but he was in the money and got some points. All because the Ford 3rd member was easy to deal with. Same thing at the drags, somebody is racing, he decides he doesn't have the correct axle ratio for that day's conditions, he wants to change ratios, if he's got a Chevy 12 bolt or Dana, its a couple hour job to change gears. If he's got a Ford 9-inch, he just pulls the axles, unbolts the 3rd member, puts in another one with a different ratio, puts the axles back in, buttons it up and away he goes. Now, lower class racers can't afford several 3rd members to be on hand, but a higher class racer that wants to change rears, he could easily have a couple of 3rd members in his trailer. as needed.
Yeah, you will see all real race cars use the Ford design third member just for that reason. The ease of setting up many different ratios and having them on hand ready to go. How fast and easy it is to change one out and by their design , they are simply stronger. This mopar guy is an idiot, they think that mopar crap is all there is, you can’t teach them anything 😂
Wow! Just when you think you know some stuff, here comes Uncle Tony! The whole thing involving interior stylists: Didn't know that. I was in the business for nearly 40 years, and am considered by a lot of people to be very knowledgeable. Nope. Every single time I watch UTG, I learn something new. Thanks, sir!
I've heard so many rumors and different stories about how much power the 9 inch takes over the 8.8 but never has anyone actually done any testing, would be a super cool video to make
Knew a guy that found a junkyard 9" rear axle out of a Lincoln Mark V that was factory rear disc. I had no idea Ford made 9" axles with rear disc. What a learning moment.
I really learned a lot from these diff videos. Your communication style is direct and informative. I have driven lots of different diffs at all levels of customization and I am confident I can explain them better now than I ever could before thanks to this differential series. Thank you for making them.
Absolutely, I think thats pretty much what tony was covering in this episode, dropout third members! The Ford 8-inch doesn't get enough love tho they can also be built very strong nowadays!
@@rustybritches6747 I'm glad to hear you like the Ford 8in. I currently am running about 340 HP/TQ on my 65. I'm going to rebuild the 8in I have and run 3:55 with track-loc. From my research they are good to 400 if you rebuild with quality parts.
@@rustybritches6747 I have put brutal amounts of horsepower and abuse on "Mostly Stock" 8-Inch rears in Mavericks and Similar Vehicles....It does NOT get nearly the love it should and interestingly I have been told that its "Far Weaker" than an 8.8 axle...And maybe for housing strength (weight capacity) but "Raw Torque" No Way! - I have destroyed many more 8.8's than 8" - Granted neither can take the 1000HP abuse that a 9" can take with same ease.
The 9" in a hot rod that is just a driver is overkill. It also is a problem in lightweight cars such as a Model A. The problem being unsprung weight. When your car is too light to hold the rear end on the ground the ride quality suffers. I have used quite a few 8" rears in lighter hot rods with good success. I have also used the 8.8 Ford rear which is basically a 12 bolt Chevy rear. Some parts interchange. The reason that Ford went with the 8.8 is for fuel economy and weight. It's a decently strong rear without the extra drag of the extra low pinion.
good to know as i am at a choice point on my build and am trying to sort throu what would be most useful and interchangeable easily but also affordable in case i constantly grenade them 😂 😂
I put an 8.8 in my ranger. So far I'm loving it. It'll probably be my go to axle for custom stuff. Right now, they're super cheap, so probably about the best bang for buck option out there.
@@qwerty2008100 I know it's an old comment but how much are the 8.8 vs the 9 inch? I live in Europe don't know what are reasonable prices for a used rear end.. building a hot rod. Leaning towards the 9 inch...
Tony thanks for this video! I had been without a car to work on for some years and back in 2000 I bought a 69 Nova(I was always a Mopar guy) from a local Chevy Super Stock racer. Already done, I did nothing to the car. Built 350, caged, tubbed, but full interior. It was a hot street car. Ran mid - high 11s on MT sportsman tires with 9" convertor, 3" exhuast no suspension aids etc. Just a well done street car. It also had a 9" rear end in it which at the time I thought was odd but I never asked the guy why he put that in a Chevy. Now all these years later I get why he did that and after learning this info from you I'd bet he was running them in his SS drag cars. Learn something new every day!
Heck I love this differential stuff, nobody ever talks about, the what, the rear end???? Lol... Thanks for the rearend info Tony, that was really great.
On my latest Street/race car project I used a strange Dana 60 which has been redesigned by strange and its many pounds lighter than the original and just as strong or stronger. I think it was less than 40 lb heavier than the eight and three quarter which I had already broken twice. And it was cheaper than a custom 9 in
Not only the added pinion support of the 9 inch....which like you said, keeps the gear from deflecting, but because of the lower pinion placement on the ring gear, the 9 inch has 4 teeth in contact at all times....versus the junk ass GM 10/12 bolts which only have two teeth in contact, and no pinion support at all. And the one piece housing does not twist like the junk ass GM rear ends that have tubes pressed into the center case, and a measly little plug weld to hold it all together.....which in a high shock load situation (drag race with manual trans, or a transbrake), has proven to be very weak and prone to breakage. And lets not forget the junk ass GM rears use tapered axles and C-clips to keep the axles in. Dangerous!
A friend of mine with a circle track car[where you are changing ratios back and forth all the time] had the best reason for running the 8 3/4 rear-"nobody borrows my damn gears!!"
NASCAR is the sol reason for the nine inch differentials success. it was exclusively used in every chassis, with an extremely low failure rate in the series. and is still used today however it's not manufactured by Ford anymore. but there are after market companies that still make every piece of the differential. back in the late fifties and early sixties before NASCAR went to one chassis for all manufacturers. they found that the nine inch rear end was bullet proof. so it became the rear end of choice when NASCAR attempted to even the playing field. by making the chassis and body templates the same for all manufacturers. and it remains that way still today. the differential is very popular with people in all forms of racing, and even in street performance use. because of it's strength which is best if used with thirty three spline axles. and that it's a drop out third member. which is handy for people who don't have a hoist to lift the vehicle. it allows a person to take the carrier (or as some people refer to it as the pumpkin.) from the vehicle over the bench and and work on it. and also the benefits can be almost endless for certain forms of racing. starting with the pre mentioned fact that it's a drop out carrier. it's pretty easy to fabricate into most vehicles. it's an AWESOME differential for someone who needs to do gear changes often. it works well for Posi Trac and fully locked needs. it's really simple to work on, anyone with a fair amount of mechanical ability can learn to setup the rear end. and they are highly adjustable for pre load, backlash, and gear gear mesh patterns, which is easier to do on the bench instead of in the vehicle. and did I mention that they are bulletproof? their real claim to fame is the three bearing pinion gear.
Thanks. Reminds me of when my old man would explain stuff to me, or when I listened in at the shop him shooting the shit with buddies in such a way that doesn't make you want to jump out a window.
The old Ford 9 inch (banjo) rear ends were used on the F-150's and Broncos until the early to mid 1980's and were very rugged and durable for towing heavy loads without problems. They were especially good for four wheel drive vehicles especially when equipped with the Trak Lock positraction unit. Most of these axles would go several hundred thousand problem free miles with minimal care. An old racers trick was to drill a drain hole in the bottom of the axle housing and tap it with a 1/8 inch pipe plug to make oil changes easier.
i ran the 9" some with the BB chevys and ponchos , we did manage to break some of them. seems like they ate spider gears pretty often if you came out hard into second esp with the 4 speed. the old 10 bolt was actually pretty good till you hit 500HP--, the 12 bolt worked pretty good, i had a mopar 8.75" in a heavy f body full of big block th-400 and a huge stall and the thing never broke. we did put a ford 8.8 in a streeter with a 425HP SBC i don't recall it giving any problems--but it was a small block in it. it was an automatic car too.
One thing you didn't mention is tha for other forms of racing, often the optimal gear ratio varies for different tracks. The removable carrier axles make changing the ratios easy. For offroad use where you can have very high torque at low speed the 9 inch is ver good. I love the removable pinion carrier, it makes setting the depth so much easier!
It's like the Big 4 Manufacturers were laying the groundwork for the Performance era of cars that were to come in the early to mid 60s already back in the Late 50's. All the engine platforms that became the big hitters for performance had their Genesis in this time, so too driveline components like Diffs and Gearboxes. Most of these Auto Execs had been Defence Staff in WW2, so they knew the virtues of Strategic Planning
The 8.8" is an almost exact copy of the Chevy 12 bolt, so... everything old is new again. That said, 8.8 inventory will be drying up in the near future. I don't think Ford has built much except maybe some F150s that use one and I think those are "weird" ones compared to all of the passenger car stuff from days gone by.
@@TheBrokenLife A 8.8 has a different pinion position than any Mopar rear . Mopar engines and transmissions are offset 1/2-1" to the passanger side of the car . this puts a compound angle on the driveshaft which shortens its life . IMO opinion anyone using an 8.8 ford is an economic reason . I'm not saying "cheap" here .
Many up here in the junkyards. People still pitching 8.8's for big dana's and ford 9's. Good for me, because it's super cheap with LSD, there's like 50 of them in any yard at any given time, parts are everywhere and a slightly built welded one is cheap and can survive 800+HP daily.
@@tomdamon7208 I wasn't speaking specifically to Mopar swaps, but usually the drive line in any car isn't directly on center. You want some amount of lateral misalignment between the front and rear universal joints to help equalize the velocity changes between them. I don't think 1" is all that extreme from what I've observed in the wild. I think Ford F trucks from the 60s and 70s had something crazy like a 4" offset. I'm also not the guy to teach a course on this subject. There's a bunch of trigonometry involved. 😆 That said, no 8.8 built in the last 20 years is going to be a direct bolt in to almost any car and I would expect customization. I absolutely agree that cost is a big factor on why guys go that way. I can buy disc brake 8.8"s pretty much as fast as I can dial the phone for almost scrap price. On a street car with 3 season tires, I doubt you'd ever break either a 8 3/4" or 8.8" without working to do it. That makes it a pretty appealing option.
@@tomdamon7208 I think some guys have been getting the explorer 8.8, shortening the long side to equal the short side, then getting one more short axle. Then they have a slightly narrowed housing for cheap
Interesting fact about right side entry and exit. It started well before the 50's. My 28 Model A has an interior lock on the drivers door and an outside key lock on the passenger door. Back then the idea was to enter and exit from the right side. Also, Ford had the rear support pinion bearing on rear axles from the 30's. The Hallibrand rear in my sprint car had the rear support bearing and it used an old Ford (1940's) ring and pinion.
Great video! When I was a young man in the 70's racing Mustangs, everyone wanted the 9 inch for street/strip cars. I did multiple swaps of 9 inch rear ends into Mustangs that came with the 8" including a 69 I owned (swapped a top loader 4 speed into it too). I've currently got a 67 390 Mustang that came stock with the 9 inch.
@@nickbonvino yea, not even all 351's got the 9. my q code 72 (351 4v) had a 8" from the factory, swapped a 9 in with a locker and 4:11's for some more fun. My dads 69 (4v 351) had a 9
For a change I agree with you. A well thought out and presented clip. The 9" was an evolution of the 8" Ford used from about 48 on. Used on medium performance applications until the 80s. Like so many I was forced to use a 9" in my road race car to get the ratios required for different tracks. Mine was built with equal length axles and I used Aussie 10 bolt 1 tonner axles cut to the length for the car. The Ford used GM axle tubes and brakes etc all interchanged. For a period I used the 10 bolt for one track and the Ford for another until I managed to find the 3 ratios in Ford centres. And you could feel the drag incurred with theFord as well as smell it!! Straight 90 oil?? Not good enough. Perfectly ok in the 10 bolt. My then oil supplier Pennzoil recomeded old vegetable based limslip [diff was a spool] and that saved the gears though stunk!! And changed after every meeting. These days I use sythetic in everything. Runs cooler and does not burn up. However 9" diffs are not really strong or efficient. Pinion is too low. Even with the pinion 'support' those diffs blow up pinion gears. In part because oil will not handle it. I have seen the pinion support break off the carrier, the little bearing explode [twice personally] and the stub break off the pinion. And with aftermarket gears that are softer simply wear out then explode. Genuine Fordn gears are far better but also more brittle. Im used to inspectn everyting very regularly. Caughtcracked gears that way before they broke. 28 spline Ford axles are made from plastic. GM ones [and later 78 series BW axles] are made from steel and seldom ever fail. Bigger is NOT better!! These days them car I dabble with is using 7.8" Borg Warner diffs with a mini spool. With 440hp so far excellent. Another 100 however??. But I have 3 diffs axle to axle that with spools owe me about $800 We never got 8.8s here in Oz. If we had I would be using them.
Finally this channel is doing the thing it can, explain why. TH-cam is full of big power now why no efficient designs, you are showing what it means to know why vs how which is much more important
I read an article many years ago talking about how Fords were breaking axle shafts on hard launches. The engineers kept trying harder and harder materials and the harder the material the easier it broke. They eventually tried a softer iron for the shafts and didn't have any more problems, what they found out was the harder axle shafts weren't flexing under load and the softer more spring like one would and not break. Doing this from memory, please correct any details, thanks!!!!
I enjoy watching Tony. I'm not much younger than him and I like the fact that he still does things with carbs and points. The younger generation has no idea how much better than the newer stuff. I'm a mechanic and car were better and more durable. Personally I feel they haven't made a good car since around 1985.
You, of course, are correct. What is allowing today's cars to rack up such as incredible miles is today's synthetic motor oil. If oil hadn't improved, today's wonder cars would be hard pressed to last much longer than 60,000 miles before needing the engine completely rebuilt.
The professor knocks it out of the park. Thank you (Uncle)Tony. for sharing your love of all things automobile, and all of the quirks that go with it, i.e., Ford 9" in. Rear Ends, and so much more. Some people would actually pay money for this knowledge, and Uncle Tony gives its; for the price of admission, just click on it. In my best Kojak (crime drama television series starring Telly Savalas) voice, Who Luv's ya baby! aired on CBS from 1973 to 1978.
Some of the strongest 9 inch axle tubes came in the Lincoln Versailles with rear disc brakes. They had to be beefed up for the added stress caused by the disc brakes. The whole thing is beefed up, all the way across, from axle bearing to axle bearing. A lot of Granadas have 9 inch rears that will fit older Torinos and possibly, 71 to 73 Mustangs too. The 1970 Torino rear springs were a perfect match. The racing rules changed to allow different brands of rears, due to available safety axles and bearings.
I’ve always wanted to know how the factories mass produced setting up the ring and pinions. A relatively precise deal to replicate, while churned out by the millions
I'd guess some sort of big precision fixture/machine that allows direct measurements of the relevant parameters, so they can set up the gear mesh directly and take all the skill out of it. I doubt they're going off pattern as anything more than a QC check, if at all.
I worked in a transmission factory back in the '80's......I won't mention the name, but the company came south to escape the unions. Set-up a brand new HUGE factory and filled it with WW2 and 1950's tech machining stations they used up north . Those old machines worked VERY well most of the time.....blew my mind.
I have a 9" as a differential demo for my truck drivetrain class. It's a scaled down copy of the larger Eaton's, Spicer's and Meritor's that are used in heavy trucks. The spigot support and detachable pinion make them easy to rebuild and adjust.
Great video Unk....I learned a lot. Back in the day, I was told the posi on the 9 inch wasn't as good as the clutch type 8 3/4 on our mopars. In an automatic hemi most came with the 8 3/4
@@oops1952 They made lots of variants of 8 3/4.My dad got his beloved 65 Coronet sedan totaled by a new American in a taxicab. The Dodge coronet was a 225 slant 6 and 3 on the tree and 250K miles that he bought new. The 3.31 to 1 8 3/4 had very thin looking ring and pinion gears and I put it in my 62 D100 slant 6 and 4speed granny as the 3.9 ate too much gas as I was freeway driving a lot. It worked fine pulling my flatbottom v-drive boat for a decade .I then put it in a 1971 D100 and ran it for another 5 years.
Good to here some one sit down and talk about this. Being a life time Mopar owner/fan, I have played with my fair share of 8-1/4, 8-3/4, 9-1/4 and Dana 60 rears. One nice thing about the ford 9 is there are aftermarket center sections that use the gm 12 bolt style ring and pinion placement. Giving you the advantages of both. When we raced dirt track cars, the drop out center section made it easier to change ratios for the track conditions.
Nice explanation Tony. The proper term for the pinion front half is called a pinion cage assy it has two tapered roller bearings in opposing each other. I agree with you on the pinion deflecting an there is a lot of pressure there but the ring gear deflects more than the pinion gear. That's why on trucks we put a thrust bolt on the centerline of the pinion in the housing an it goes flat against the ring gear to reduce the deflection. That would be a cool mod to do to these car diffs.
If you want to see the rear that possibly inspired the Ford engineers 30 years later, check out a Packard from the late 1920's. In 1926, Packard was the first true Hypoid rear end, and it had all the features that Ford put in the 9 inch. Straddle mounted pinion, 2 inches lower than ring gear centerline, in a beefy drop out third member. Pretty cool for almost 100 years ago !
Well you know Packards only exist because they wrote Ford telling him how to make his car better and last longer and Ford told them if they knew better than him they should build their own so they did! LOL
Being able to assemble the pinion and bearing separately is, in my opinion, a lot easier to set the bearing preload. I've seen the pinion support bearing in heavier light truck and medium duty differentials. Chevy liked it. Coming from the truck world, I want to point out that there are "high pinion" differentials that put the pinion up about 2 o'clock on the ring gear, which is going to have as much drag as a 4 o'clock placement. "Higher" being more efficient stops at 3 o'clock. Just 'cause someone right now is thinking that a 12 o'clock would be best...
I have never owned a Ford 9in but always heard about them. Now I know why they are spoken so highly of. Thanks for the education. Great information. Now I know why they are so good and why I will never need one.
Some Imperials had rear discs yeah, but it would have been a Chrysler 9 1/4 in that year. No full size Mopar had a Dana, except the 1967-68 4 speed cars that used the Dana 53.
If you have a vehicle that you want to use it on the street, road trips and drag racing the 9" rear is one of the best because you can pull the axles and remove the center section and change the gear ratio without the process of setting up the lash under the vehicle.
My Father bought a 1961 Chevy Belaire with a 283 engine 3:73 gears three on the tree three speed Borg Warner Trans mission with Overdrive.. it had a T-handle on the dash you could pull out for over drive and push in for direct drive .. you could split 2nd and third gear thus you could shift it like a 5 speed .. and with overdrive get very good mpg ..
Put a match set of axles from an early Bronco in my jeep. The 9 in the rear with a high 44 in the front. It was all about "shock" load. Low speed, high torque with shock loads when the tires loose traction and then grab. Never broke the stock 35 spline BB, broke a few u joints up front....
The 8.8 is still a pretty strong rear too. One of the last cars they ran the old 8.8 on was the Trinity 5.8 powered GT500. I don't remember hearing anyone complaining about having problems with them on those cars. I've also seen guys mod their cars/trucks with the 8.8 to 800-1000hp and again don't remember hearing anyone complain about them breaking. I'm sure once you start running 8's at the dragstrip that story might change, but for any street car you can't go wrong. Great on fuel with the right ratio too.
I have a 1950 Willys Jeepster which I put an eight inch Ford rear about 20 years ago....The right rear bearing leaked and a sleeve was not available so about eight or ten years ago I changed it to an 8.8 inch from about a 1980 Ford Explorer....I have had no problems with the 8.8....
Your case makes sense however this was pioneered by Chevrolet in 1937 as they had the same motivation . By this time in history bodies were being lower on the frame to improve streamlining . And there is a picture I have seen on You Tube where the driveshaft runs through the passenger compartment . However it was considered impracticable due to loss of floor space [ not to mention hazardous to the occupants of the car ] . So they showed how lowering the pinion gear moved the driveshaft down . This can be found by searching Jim Handy Chevrolet differential 1937 , this is also for the beginner the best explanation of how a differential works I have ever seen . Take a look you will agree .
I mentioned the Cad/Lassale rear, which is another example of early dropped pinion design, but this video is about the 9 inch and it the specific reasons it is stronger than the others
I think these differential videos are great. Learned a lot. It would be cool if you talked about the Dana 60's and 12 Bolt Corporate more since you can find thousands of them in the rears of older trucks. They are probably 8 bolts lug pattern, but are still usable for a lot of guys on a budget.
The 14 bolt corporate is the most durable due to the third pinon bearing that does prevent pinon gear deflection under shock loading such as axle hop or tire shake put a truetrac Detroit in it and use the skinny pedal with reckless abandon and the first thing to break will be an axleshaft replace those with some cromoly ones and tada bullet proof rearend
True. Have one in my daily C3500. Thinking about machining my own 8 bolt to max 5 adapters and running sprint car wheels and drag tires on my hotrod project just because I already know it so well and know it's about bomb proof, especially like you said, with chromoly axles, which takes 10 minutes to swap in lol.
In the middle 80’s circle track racers embraced the 9” because of the drop out centers, racers could tune the rpm of the engine to the racetracks quickly. This was especially true of classes that were not allowed to use a quick change rearend.
Another great, informative video from UTG - now I want to go down the rabbit hole on IRS differentials and find out what their plusses and minuses are...
I like the dana 60 it held up great in my 1967 GTX 4-speed put the hammer down many times and changed a few clutches. I got fairly quick with that inland shifter
I have been beating on a 9 inch with stock shafts in my 6800lb cherokee. 37s, beadlocks, Detroit locker. It takes way more than it should. But it for sure drags. You can feel it. But I won't ever break the gear.. stock shafts eventually
That was a very good technical presentation! Once again just a accurate assessment of pros and cons, with a interesting side of history. Bravo! You can tell I'm a dinosaur, I still use the old GM 12 bolt jackpot. The Pontiac-Olds that was top dog in the 60's, in most of your high horsepower classes. They were never plentiful or cheap, but if you were running a Chevy gasser, the only way to go. The Ford is the way to go now, given the market. Great lecture!
Another good thing about it is you can have multiple gear ratios in different carriers and depending on what you are doing you can swap it out. Put steep gears in depending on the track to get different results. Same with the Chrysler center you have there on the table.
So back in the day, the 9" Ford was designed primarily for the Lincoln. Think back seat in the Kennedy convertible. As close to zero drive shaft tunnel as possible. 2 piece drive shaft where the slope was in the front half and the back half was flat under the floor w/ a very small tunnel. I have always preferred the 8 3/4 Chrysler for bigger power and the 8" Ford for smaller power cars. Add a thread in brass rod in an 8" Ford that rides 0.010" off the side of the ring gear opposite the pinion engagement and it's pretty darn beefy. If you are over 400 HP and have enough tire to mean something, 8 3/4 all the way. Either is more efficient than a 9" 🙃
Off topic here. DDs speed shop has talked about taking a Chevy Nomad on the power tour, not the Uncle Tony charger. Has your plans changed on the project since it may not be taking a long drive in the summer?
I wanted to put a Ford 9" in my P3 - Permanent Pacer Project - but I'm currently rocking a Ford 8.8" - because a 9" Simply Won't Fit. Equipped w/a torque-biasing diff, backing up an LS3/5L50E combination, it's more than entertaining enough in the very SWB Pacer.
hello from Australia UTG ,greatest auto channel on youtube , i have a 351W up front followed by a top loader and i really wanted a 9 inch LSD in back and get rid off that single spinning Falcon diff before it lets go ,i purchased a 9 LSD and paid a mechanic to fit it as i had just gone through a herniated disc and needed to do physio ,dropped off in morning and picked up in the afternoon and it was awful ,everytime i made a sharpish turn in 1st or 2nd one wheel would almost stop turning and churp churp especially around a roundabout ,i took it back and the mechanic said thats how it should be ,thats BS all i wanted was two wheels to spin ,how can i stop this wheel doing this as i made a bit of a goose of myself and the mechanic barred me from hes workshop
i remember when we had about 20 ford 9inch rear ends laying everywhere we swapped our fuel altered to a bullet proof 9 inch had one think it was from a bronco it fit perfect in an s10 you could buy mini spools for dirt cheap instead of welding spider gears. thos were the days
Stock, the 9" isn't particularly strong. It's the aftermarket that makes it great combined with the removable centre, which means it's so damn convenient. Because it is so well supported in the aftermarket, parts are relatively cheap and available.
Had the 9" in my 72 Grand Torino Sport Fastback with the Cleveland, trucks, & T Birds 76 thru 78)4 of them/racing & street. The Torino 9" was used up so I took one out of a Police car a guy had in his salvage yard. It was a 2:50:1 ratio. That Torino then had some long highway legs for fast cruising without high RPM. And those 9" rears held up plus easy to work on. P.S. They need to raise the ground clearance on cars cause our roads are crap. Every entrance into or out of a business in town has right at a 45 degree v notch from the street to the driveways or parking lots. Everywhere you see gouging in the pavement because of this & damage to the cars. Plus thousands of miles of gravel roads throughout the State.
Awesome video Uncle Tony. One thing I did not know until recently is when you purchase a brand new 9 inch these days more often than not they will be noisy because of how modern gears are machined.
As always, Uncle Tony, I learned a ton from this video! In fact, it made me think of "Sarah-N-Tune" who's stuffing a Toyota V8 in a Corolla and what Toyota transmission and rear axle she could use to make all work out. I guess I'd appreciate more reasons why you'd want a Ford over a GM over a Mopar over a Dana over a etc.
I've busted the pinion/ring gear on a Chevy 10 bolt, did it again on a Dana 44 in a CJ5, had the spider gear retainer pin slip out and hit the pinion on a Dana 60 locking it up on me, full floater, so I pulled the axles and towed it home.
I love 8- 3/4s! I have an 1980 D150 with the 9- 1/4inch with 2.76 .Like a GM it has the C-locks holding the axle in. They are sloppy with only 100k miles and my fingers are crossed. I tried switching the axle and spiders to new parts with no uptake in the slop. I am looking for a 72-74 D100 junker with an 8 3/4 housing.I like the old Timken tapered roller bearings with adjuters by shim on 64 and older or threaded doohickey on the right side 65 on up. My buddy had a hot 62 Chevy pickup and got on it hard and a c-lock jumped out and the axle came loose and wiped out his new purple metalflake paint job on the left side of the bed. I am not enamored of any Mopar rear ends witha tin bolt on cover.
We used the Chrysler for years, it lets you out the motor up a little higher in the chassis with out so much tilt. It’s plenty strong as long as you don’t get into tire shake
I have a question about an 8.8 rear dif from a 04 Cobra It only has 25000 miles but I had to replace the crush sleeve and the pinion flange Did not get The reading on the rotational resistance before I took it apart. I have it in between the spec that Ford recommends for the preload 8 to 14 around 10 or 12 Ib-in for me. Everything feels smooth when I rotate it And I used gear marking compound To see the pattern at least. My question is with such low miles should I expect a wining noise from having reset the preload and not knowing what the previous spec was. And what might be a way to go about Getting it to stop. Thanks man also always find your videos super helpful And I end up learning a lot every time keep up the great work👍👍
Crush sleeves don't go bad unless excessive wheel hop occurs or no mercy reverseis ,neutral drop on TH-cam ifn u don't kno what dat is, both are driver error unless a mechanic over tightened the pinion nut after a seal change
The 9 inch Ford really came into prominence NOT in NHRA and drag racing but through those good old boys down South.....NASCAR. When the roundy round boys figured out that they could make a full floater rear end out of these things and then discovered rear end coolers they became mandatory if you turned left. They are still used in a LOT of circle track cars due to strength, gear ratios and many other reasons. They are MUCH easier to set up than a 12 inch chevy and more durable.
Well hell, Now I want you to go deep on the Dana 60. Pros and cons. Where does it get its legendary strength? Where was it popular in racing? I get so much out of these vids where you nerd out and a specific component. U joints sizes and strengths and driveshafts materials balancing yoke sizes.
In Trans Am Javelin we had AMC Salisbury style rear end, Hotchkiss makes gear swaps much easier,(we usually changed complete rear end) but out on the course Salisbury is measurably more efficient and runs cooler but both required coolers
Hey uncle Tony, we appreciate you much! my 68' Fairlane 500 fastback has the 8in rear differential. originally came with 302. im installing a 390 and was thinking of a 9in swap but after watching this im not sure..
Just the fact that you can pull the carrier out and set it up on a table and not laying on the ground under your vehicle (unless you have a lift, or take the rear end out, etc) is very important to me.
I strongly agree. I pretty much refuse to setup gears under a vehicle.
As a 12 bolt owner, I do find dropping the whole rear a tad inconvenient. But so is trying to shim things in place [I don't have the luxury of a lift].
Plus you can have different center section to swap for different types of racing.
Very interesting vid😎👍
The much more available used and cheap Ford 8.8" is popular...
Is the Ford 9 3/4" used in SUVs stronger than the 9"?
Getting into cars from the curb side used to be the LAW! In old 1940's-50's shows, most people, even drivers, get in from the curb side and slide over...
I remember when you could go into the junkyard and get a 9 inch Ford rear axle for under a hundred bucks and you had choices in gear ratios and widths... Man I'm getting old!🤓
One thing about the Ford 9-inch that sticks with me to this day, it happened 25-30 years ago or more, it was a NASCAR race on TV that I was watching in real time. Bobbie Allison pulled into the pits, and something in the rear broke for some reason, it was a fluke. There was a yellow flag at the time and everybody pulled into the pits for tires and fuel. Something in Allisons 3rd member broke. The crew chief immediately sent one crew member to their transporter to get another 3rd member, and as he was gone, the rest of the crew jacked up the car, took off the tires, pulled out the axles, took off the 3rd member, then the man that was sent to get another 3rd member got back to the pits, they put in a whole new 3rd member, reassembled the axle, Allison got back on the track, and never lost a lap, because everybody was in for gas and tires. He was at the very rear of the same lap, but it was the same lap. If he'd been running anybody else's axle, they would have had to disassemble the center section with a spreader, and everything else involved with a Chevy 12-bolt or a Dana 44 or 60, and he would have been screwed. But because the Ford 3rd member was pre-assembled, it was easy(ier) to deal with. He didn't win the race, but he was in the money and got some points. All because the Ford 3rd member was easy to deal with. Same thing at the drags, somebody is racing, he decides he doesn't have the correct axle ratio for that day's conditions, he wants to change ratios, if he's got a Chevy 12 bolt or Dana, its a couple hour job to change gears. If he's got a Ford 9-inch, he just pulls the axles, unbolts the 3rd member, puts in another one with a different ratio, puts the axles back in, buttons it up and away he goes. Now, lower class racers can't afford several 3rd members to be on hand, but a higher class racer that wants to change rears, he could easily have a couple of 3rd members in his trailer. as needed.
Yeah, you will see all real race cars use the Ford design third member just for that reason. The ease of setting up many different ratios and having them on hand ready to go. How fast and easy it is to change one out and by their design , they are simply stronger. This mopar guy is an idiot, they think that mopar crap is all there is, you can’t teach them anything 😂
Wow!
Just when you think you know some stuff, here comes Uncle Tony! The whole thing involving interior stylists: Didn't know that.
I was in the business for nearly 40 years, and am considered by a lot of people to be very knowledgeable.
Nope.
Every single time I watch UTG, I learn something new.
Thanks, sir!
The Rover differential out of a series Land Rover has the pinion at about 3 o'clock. It's good for almost 50hp.
I've heard so many rumors and different stories about how much power the 9 inch takes over the 8.8 but never has anyone actually done any testing, would be a super cool video to make
Knew a guy that found a junkyard 9" rear axle out of a Lincoln Mark V that was factory rear disc. I had no idea Ford made 9" axles with rear disc. What a learning moment.
I really learned a lot from these diff videos. Your communication style is direct and informative. I have driven lots of different diffs at all levels of customization and I am confident I can explain them better now than I ever could before thanks to this differential series. Thank you for making them.
Stylist hate engineers. Engineers hate stylist. Mechanics hate both . It's a beautiful world .
Strange Engineering makes a 9” center with 12 bolt pinion placement for Stock and Super Stock for the reasons you mentioned.
A conversation with your Uncle saves you time & money! Thanks Uncle Tony
For someone with minor knowledge on rear ends this is a great video
Another benefit of the 8.75 and 9.0 inch is the drop out center section. The 12 bolt is a PITA to switch gears.
Absolutely, I think thats pretty much what tony was covering in this episode, dropout third members! The Ford 8-inch doesn't get enough love tho they can also be built very strong nowadays!
@@rustybritches6747 I'm glad to hear you like the Ford 8in. I currently am running about 340 HP/TQ on my 65. I'm going to rebuild the 8in I have and run 3:55 with track-loc. From my research they are good to 400 if you rebuild with quality parts.
@@rustybritches6747 I have put brutal amounts of horsepower and abuse on "Mostly Stock" 8-Inch rears in Mavericks and Similar Vehicles....It does NOT get nearly the love it should and interestingly I have been told that its "Far Weaker" than an 8.8 axle...And maybe for housing strength (weight capacity) but "Raw Torque" No Way! - I have destroyed many more 8.8's than 8" - Granted neither can take the 1000HP abuse that a 9" can take with same ease.
Tony, sometimes it's just like being at school....you learn something every day.
Well done!
The 9" in a hot rod that is just a driver is overkill. It also is a problem in lightweight cars such as a Model A. The problem being unsprung weight. When your car is too light to hold the rear end on the ground the ride quality suffers. I have used quite a few 8" rears in lighter hot rods with good success. I have also used the 8.8 Ford rear which is basically a 12 bolt Chevy rear. Some parts interchange. The reason that Ford went with the 8.8 is for fuel economy and weight. It's a decently strong rear without the extra drag of the extra low pinion.
True, the pinion bearings in the 8.8 and the 12 bolt are the same. People sleep on the 8.8s
I have the Ford 9" rear in my 1974 Lincoln mark VI
I use the 8.8 in my little street rod. After market gears are no problem and they're bullet proof. Thanks for the tutorial Professor Tony.
good to know as i am at a choice point on my build and am trying to sort throu what would be most useful and interchangeable easily but also affordable in case i constantly grenade them 😂 😂
I put an 8.8 in my ranger. So far I'm loving it. It'll probably be my go to axle for custom stuff. Right now, they're super cheap, so probably about the best bang for buck option out there.
@@qwerty2008100 I know it's an old comment but how much are the 8.8 vs the 9 inch? I live in Europe don't know what are reasonable prices for a used rear end.. building a hot rod. Leaning towards the 9 inch...
My old man has an early 70’s altered and it came with a 57 Olds style rear end. Those were pretty popular amongst GM guys for a while too.
Yep the mighty Olds
Will be pulling the Ford 9 inch out of my 55 Chevy to put an olds 9.3 I acquired..
The only good thing about a 9in is there cheap and plentiful
No wonder I never broke the rear end in my '57 Olds 98 StarFire back in the 1960's...
Tony thanks for this video! I had been without a car to work on for some years and back in 2000 I bought a 69 Nova(I was always a Mopar guy) from a local Chevy Super Stock racer. Already done, I did nothing to the car. Built 350, caged, tubbed, but full interior. It was a hot street car. Ran mid - high 11s on MT sportsman tires with 9" convertor, 3" exhuast no suspension aids etc. Just a well done street car. It also had a 9" rear end in it which at the time I thought was odd but I never asked the guy why he put that in a Chevy. Now all these years later I get why he did that and after learning this info from you I'd bet he was running them in his SS drag cars. Learn something new every day!
Heck I love this differential stuff, nobody ever talks about, the what, the rear end???? Lol...
Thanks for the rearend info Tony, that was really great.
On my latest Street/race car project I used a strange Dana 60 which has been redesigned by strange and its many pounds lighter than the original and just as strong or stronger. I think it was less than 40 lb heavier than the eight and three quarter which I had already broken twice. And it was cheaper than a custom 9 in
Not only the added pinion support of the 9 inch....which like you said, keeps the gear from deflecting, but because of the lower pinion placement on the ring gear, the 9 inch has 4 teeth in contact at all times....versus the junk ass GM 10/12 bolts which only have two teeth in contact, and no pinion support at all.
And the one piece housing does not twist like the junk ass GM rear ends that have tubes pressed into the center case, and a measly little plug weld to hold it all together.....which in a high shock load situation (drag race with manual trans, or a transbrake), has proven to be very weak and prone to breakage.
And lets not forget the junk ass GM rears use tapered axles and C-clips to keep the axles in. Dangerous!
A friend of mine with a circle track car[where you are changing ratios back and forth all the time] had the best reason for running the 8 3/4 rear-"nobody borrows my damn gears!!"
NASCAR is the sol reason for the nine inch differentials success. it was exclusively used in every chassis, with an extremely low failure rate in the series. and is still used today however it's not manufactured by Ford anymore. but there are after market companies that still make every piece of the differential. back in the late fifties and early sixties before NASCAR went to one chassis for all manufacturers. they found that the nine inch rear end was bullet proof. so it became the rear end of choice when NASCAR attempted to even the playing field. by making the chassis and body templates the same for all manufacturers. and it remains that way still today. the differential is very popular with people in all forms of racing, and even in street performance use. because of it's strength which is best if used with thirty three spline axles. and that it's a drop out third member. which is handy for people who don't have a hoist to lift the vehicle. it allows a person to take the carrier (or as some people refer to it as the pumpkin.) from the vehicle over the bench and and work on it. and also the benefits can be almost endless for certain forms of racing. starting with the pre mentioned fact that it's a drop out carrier. it's pretty easy to fabricate into most vehicles. it's an AWESOME differential for someone who needs to do gear changes often. it works well for Posi Trac and fully locked needs. it's really simple to work on, anyone with a fair amount of mechanical ability can learn to setup the rear end. and they are highly adjustable for pre load, backlash, and gear gear mesh patterns, which is easier to do on the bench instead of in the vehicle. and did I mention that they are bulletproof? their real claim to fame is the three bearing pinion gear.
Thanks. Reminds me of when my old man would explain stuff to me, or when I listened in at the shop him shooting the shit with buddies in such a way that doesn't make you want to jump out a window.
I have been using ford 9" N case rears sense 1971 and haven't had 1 second of problems with them. Excellent rear end.
The old Ford 9 inch (banjo) rear ends were used on the F-150's and Broncos until the early to mid 1980's and were very rugged and durable for towing heavy loads without problems. They were especially good for four wheel drive vehicles especially when equipped with the Trak Lock positraction unit. Most of these axles would go several hundred thousand problem free miles with minimal care. An old racers trick was to drill a drain hole in the bottom of the axle housing and tap it with a 1/8 inch pipe plug to make oil changes easier.
i ran the 9" some with the BB chevys and ponchos , we did manage to break some of them. seems like they ate spider gears pretty often if you came out hard into second esp with the 4 speed. the old 10 bolt was actually pretty good till you hit 500HP--, the 12 bolt worked pretty good, i had a mopar 8.75" in a heavy f body full of big block th-400 and a huge stall and the thing never broke. we did put a ford 8.8 in a streeter with a 425HP SBC i don't recall it giving any problems--but it was a small block in it. it was an automatic car too.
One thing you didn't mention is tha for other forms of racing, often the optimal gear ratio varies for different tracks. The removable carrier axles make changing the ratios easy. For offroad use where you can have very high torque at low speed the 9 inch is ver good. I love the removable pinion carrier, it makes setting the depth so much easier!
It's like the Big 4 Manufacturers were laying the groundwork for the Performance era of cars that were to come in the early to mid 60s already back in the Late 50's. All the engine platforms that became the big hitters for performance had their Genesis in this time, so too driveline components like Diffs and Gearboxes. Most of these Auto Execs had been Defence Staff in WW2, so they knew the virtues of Strategic Planning
Keep going with this rear-end series! I'm learning a lot. I know there's more about it you can talk about. Thanks.
Ford 8.8 is the new junkyard jewel now
The 8.8" is an almost exact copy of the Chevy 12 bolt, so... everything old is new again. That said, 8.8 inventory will be drying up in the near future. I don't think Ford has built much except maybe some F150s that use one and I think those are "weird" ones compared to all of the passenger car stuff from days gone by.
@@TheBrokenLife A 8.8 has a different pinion position than any Mopar rear . Mopar engines and transmissions are offset 1/2-1" to the passanger side of the car . this puts a compound angle on the driveshaft which shortens its life . IMO opinion anyone using an 8.8 ford is an economic reason . I'm not saying "cheap" here .
Many up here in the junkyards. People still pitching 8.8's for big dana's and ford 9's. Good for me, because it's super cheap with LSD, there's like 50 of them in any yard at any given time, parts are everywhere and a slightly built welded one is cheap and can survive 800+HP daily.
@@tomdamon7208 I wasn't speaking specifically to Mopar swaps, but usually the drive line in any car isn't directly on center. You want some amount of lateral misalignment between the front and rear universal joints to help equalize the velocity changes between them. I don't think 1" is all that extreme from what I've observed in the wild. I think Ford F trucks from the 60s and 70s had something crazy like a 4" offset. I'm also not the guy to teach a course on this subject. There's a bunch of trigonometry involved. 😆
That said, no 8.8 built in the last 20 years is going to be a direct bolt in to almost any car and I would expect customization. I absolutely agree that cost is a big factor on why guys go that way. I can buy disc brake 8.8"s pretty much as fast as I can dial the phone for almost scrap price. On a street car with 3 season tires, I doubt you'd ever break either a 8 3/4" or 8.8" without working to do it. That makes it a pretty appealing option.
@@tomdamon7208 I think some guys have been getting the explorer 8.8, shortening the long side to equal the short side, then getting one more short axle. Then they have a slightly narrowed housing for cheap
Great video! I know what your talking about, but, love the way you explained it. Had forgotten about the 57-59 Ford floorpan issues,, right on,,,K
Great video! Everyone seems to think the 9" is the holy grail, but everything depends on application.
assembly on a convenient work surface and NOT under a vehicle IS the holy grail!
Interesting fact about right side entry and exit. It started well before the 50's. My 28 Model A has an interior lock on the drivers door and an outside key lock on the passenger door. Back then the idea was to enter and exit from the right side. Also, Ford had the rear support pinion bearing on rear axles from the 30's. The Hallibrand rear in my sprint car had the rear support bearing and it used an old Ford (1940's) ring and pinion.
Great video! When I was a young man in the 70's racing Mustangs, everyone wanted the 9 inch for street/strip cars. I did multiple swaps of 9 inch rear ends into Mustangs that came with the 8" including a 69 I owned (swapped a top loader 4 speed into it too). I've currently got a 67 390 Mustang that came stock with the 9 inch.
Mustangs came with 9" up through 73, didn't they?
Depending on engine size…351 or bigger got the 9 inch
@@nickbonvino yea, not even all 351's got the 9. my q code 72 (351 4v) had a 8" from the factory, swapped a 9 in with a locker and 4:11's
for some more fun. My dads 69 (4v 351) had a 9
Awesome video, Unc! One more history of the Ford 8.8 since you mentioned it 👏
For a change I agree with you. A well thought out and presented clip.
The 9" was an evolution of the 8" Ford used from about 48 on. Used on medium performance applications until the 80s.
Like so many I was forced to use a 9" in my road race car to get the ratios required for different tracks.
Mine was built with equal length axles and I used Aussie 10 bolt 1 tonner axles cut to the length for the car.
The Ford used GM axle tubes and brakes etc all interchanged.
For a period I used the 10 bolt for one track and the Ford for another until I managed to find the 3 ratios in Ford centres. And you could feel the drag incurred with theFord as well as smell it!! Straight 90 oil?? Not good enough. Perfectly ok in the 10 bolt. My then oil supplier Pennzoil recomeded old vegetable based limslip [diff was a spool] and that saved the gears though stunk!! And changed after every meeting. These days I use sythetic in everything. Runs cooler and does not burn up.
However 9" diffs are not really strong or efficient. Pinion is too low. Even with the pinion 'support' those diffs blow up pinion gears. In part because oil will not handle it. I have seen the pinion support break off the carrier, the little bearing explode [twice personally] and the stub break off the pinion. And with aftermarket gears that are softer simply wear out then explode. Genuine Fordn gears are far better but also more brittle. Im used to inspectn everyting very regularly. Caughtcracked gears that way before they broke.
28 spline Ford axles are made from plastic. GM ones [and later 78 series BW axles] are made from steel and seldom ever fail. Bigger is NOT better!!
These days them car I dabble with is using 7.8" Borg Warner diffs with a mini spool. With 440hp so far excellent. Another 100 however??. But I have 3 diffs axle to axle that with spools owe me about $800
We never got 8.8s here in Oz. If we had I would be using them.
Thanks for your comment.
Finally this channel is doing the thing it can, explain why. TH-cam is full of big power now why no efficient designs, you are showing what it means to know why vs how which is much more important
I read an article many years ago talking about how Fords were breaking axle shafts on hard launches. The engineers kept trying harder and harder materials and the harder the material the easier it broke. They eventually tried a softer iron for the shafts and didn't have any more problems, what they found out was the harder axle shafts weren't flexing under load and the softer more spring like one would and not break. Doing this from memory, please correct any details, thanks!!!!
I enjoy watching Tony. I'm not much younger than him and I like the fact that he still does things with carbs and points. The younger generation has no idea how much better than the newer stuff. I'm a mechanic and car were better and more durable. Personally I feel they haven't made a good car since around 1985.
You, of course, are correct. What is allowing today's cars to rack up such as incredible miles is today's synthetic motor oil. If oil hadn't improved, today's wonder cars would be hard pressed to last much longer than 60,000 miles before needing the engine completely rebuilt.
Reminds me of the time a kid told me his car had a 9" 12 bolt.
The professor knocks it out of the park. Thank you (Uncle)Tony. for sharing your love of all things automobile, and all of the quirks that go with it, i.e., Ford 9" in. Rear Ends, and so much more. Some people would actually pay money for this knowledge, and Uncle Tony gives its; for the price of admission, just click on it. In my best Kojak (crime drama television series starring Telly Savalas) voice, Who Luv's ya baby! aired on CBS from 1973 to 1978.
Some of the strongest 9 inch axle tubes came in the Lincoln Versailles with rear disc brakes. They had to be beefed up for the added stress caused by the disc brakes. The whole thing is beefed up, all the way across, from axle bearing to axle bearing. A lot of Granadas have 9 inch rears that will fit older Torinos and possibly, 71 to 73 Mustangs too. The 1970 Torino rear springs were a perfect match. The racing rules changed to allow different brands of rears, due to available safety axles and bearings.
Derek from Vice Grip Garage just put one in his 35 Ford
Thanks Tony, a Very Interesting article, I did not know all that about the Ford 9 inch !
Thanks for the lesson !
I’ve always wanted to know how the factories mass produced setting up the ring and pinions. A relatively precise deal to replicate, while churned out by the millions
I think they have some sort of a machine tool.
I'd guess some sort of big precision fixture/machine that allows direct measurements of the relevant parameters, so they can set up the gear mesh directly and take all the skill out of it. I doubt they're going off pattern as anything more than a QC check, if at all.
I worked in a transmission factory back in the '80's......I won't mention the name, but the company came south to escape the unions.
Set-up a brand new HUGE factory and filled it with WW2 and 1950's tech machining stations they used up north . Those old machines worked VERY well most of the time.....blew my mind.
Still set up with engineers ink to check
I have a 9" as a differential demo for my truck drivetrain class. It's a scaled down copy of the larger Eaton's, Spicer's and Meritor's that are used in heavy trucks. The spigot support and detachable pinion make them easy to rebuild and adjust.
Great video Unk....I learned a lot. Back in the day, I was told the posi on the 9 inch wasn't as good as the clutch type 8 3/4 on our mopars. In an automatic hemi most came with the 8 3/4
@@MrSwinger1 I picked up an 8 3/4 from a wrecking yard that had 4 spider gears. I wondered what it came out of.
@@oops1952 They made lots of variants of 8 3/4.My dad got his beloved 65 Coronet sedan totaled by a new
American in a taxicab. The Dodge coronet was a 225 slant 6 and 3 on the tree and 250K miles that he bought new. The 3.31 to 1 8 3/4 had very thin looking ring and pinion gears and I put it in my 62 D100 slant 6 and 4speed granny as the 3.9 ate too much gas as I was freeway driving a lot. It worked fine pulling my flatbottom v-drive boat for a decade .I then put it in a 1971 D100 and ran it for another 5 years.
The Detroit Locker changed that.
I am amazed at how much this person knows. Next video will be about drag coefficient of various antennas.Tony, respect to you, I am amazed.
Good to here some one sit down and talk about this. Being a life time Mopar owner/fan, I have played with my fair share of 8-1/4, 8-3/4, 9-1/4 and Dana 60 rears. One nice thing about the ford 9 is there are aftermarket center sections that use the gm 12 bolt style ring and pinion placement. Giving you the advantages of both. When we raced dirt track cars, the drop out center section made it easier to change ratios for the track conditions.
Thanks for the tech Tony up until now I thought a 9-inch was the optimal choice for everything
Nice explanation Tony. The proper term for the pinion front half is called a pinion cage assy it has two tapered roller bearings in opposing each other. I agree with you on the pinion deflecting an there is a lot of pressure there but the ring gear deflects more than the pinion gear. That's why on trucks we put a thrust bolt on the centerline of the pinion in the housing an it goes flat against the ring gear to reduce the deflection. That would be a cool mod to do to these car diffs.
If you want to see the rear that possibly inspired the Ford engineers 30 years later, check out a Packard from the late 1920's. In 1926, Packard was the first true Hypoid rear end, and it had all the features that Ford put in the 9 inch. Straddle mounted pinion, 2 inches lower than ring gear centerline, in a beefy drop out third member. Pretty cool for almost 100 years ago !
Well you know Packards only exist because they wrote Ford telling him how to make his car better and last longer and Ford told them if they knew better than him they should build their own so they did! LOL
Being able to assemble the pinion and bearing separately is, in my opinion, a lot easier to set the bearing preload.
I've seen the pinion support bearing in heavier light truck and medium duty differentials. Chevy liked it.
Coming from the truck world, I want to point out that there are "high pinion" differentials that put the pinion up about 2 o'clock on the ring gear, which is going to have as much drag as a 4 o'clock placement. "Higher" being more efficient stops at 3 o'clock. Just 'cause someone right now is thinking that a 12 o'clock would be best...
I have never owned a Ford 9in but always heard about them. Now I know why they are spoken so highly of. Thanks for the education. Great information. Now I know why they are so good and why I will never need one.
My ‘75 imperial had a Dana 60 disc brake rear end
Some Imperials had rear discs yeah, but it would have been a Chrysler 9 1/4 in that year. No full size Mopar had a Dana, except the 1967-68 4 speed cars that used the Dana 53.
@@360dodge OK gr00mer I didn’t know my own car but you do? Bwahahaha
@@bobthompson4133 apparently you didn’t, no.
That was the best description of rear differentials , you did a good job at explaining the efficiency of the many choices.
If you have a vehicle that you want to use it on the street, road trips and drag racing the 9" rear is one of the best because you can pull the axles and remove the center section and change the gear ratio without the process of setting up the lash under the vehicle.
Good one Tony, I've had several 9" and still have one in a bronco...Rock solid !
My Father bought a 1961 Chevy Belaire with a 283 engine 3:73 gears three on the tree three speed Borg Warner Trans mission with Overdrive.. it had a T-handle on the dash you could pull out for over drive and push in for direct drive .. you could split 2nd and third gear thus you could shift it like a 5 speed .. and with overdrive get very good mpg ..
14 bolt full float chev has that extra pinion bearing too.
4x4 guys love em.
Rock bouncers and buggies all have them!
Put a match set of axles from an early Bronco in my jeep. The 9 in the rear with a high 44 in the front. It was all about "shock" load. Low speed, high torque with shock loads when the tires loose traction and then grab. Never broke the stock 35 spline BB, broke a few u joints up front....
The 8.8 is still a pretty strong rear too. One of the last cars they ran the old 8.8 on was the Trinity 5.8 powered GT500. I don't remember hearing anyone complaining about having problems with them on those cars. I've also seen guys mod their cars/trucks with the 8.8 to 800-1000hp and again don't remember hearing anyone complain about them breaking. I'm sure once you start running 8's at the dragstrip that story might change, but for any street car you can't go wrong. Great on fuel with the right ratio too.
I have a 1950 Willys Jeepster which I put an eight inch Ford rear about 20 years ago....The right rear bearing leaked and a sleeve was not available so about eight or ten years ago I changed it to an 8.8 inch from about a 1980 Ford Explorer....I have had no problems with the 8.8....
Your case makes sense however this was pioneered by Chevrolet in 1937 as they had the same motivation . By this time in history bodies were being lower on the frame to improve streamlining . And there is a picture I have seen on You Tube where the driveshaft runs through the passenger compartment . However it was considered impracticable due to loss of floor space [ not to mention hazardous to the occupants of the car ] . So they showed how lowering the pinion gear moved the driveshaft down . This can be found by searching Jim Handy Chevrolet differential 1937 , this is also for the beginner the best explanation of how a differential works I have ever seen . Take a look you will agree .
I mentioned the Cad/Lassale rear, which is another example of early dropped pinion design, but this video is about the 9 inch and it the specific reasons it is stronger than the others
I think these differential videos are great. Learned a lot. It would be cool if you talked about the Dana 60's and 12 Bolt Corporate more since you can find thousands of them in the rears of older trucks. They are probably 8 bolts lug pattern, but are still usable for a lot of guys on a budget.
Yeah , I have a factory big block 70 Dodge truck with the 8 lug Dana 60 that I plan on swapping the Eaton locker and 5 lug axles into.
In Chevy pickups the 1/2 tons would have a 12 bolt ,6 lug axle, and 3/4 ton and up would have the 14 bolt, 8 lug axle. From about the 70's up.
These hypoid gear axles had been around forever on bigger trucks prior. Ford and chrysler both just copied the bigger rockwell designs.
The 14 bolt corporate is the most durable due to the third pinon bearing that does prevent pinon gear deflection under shock loading such as axle hop or tire shake put a truetrac Detroit in it and use the skinny pedal with reckless abandon and the first thing to break will be an axleshaft replace those with some cromoly ones and tada bullet proof rearend
True. Have one in my daily C3500. Thinking about machining my own 8 bolt to max 5 adapters and running sprint car wheels and drag tires on my hotrod project just because I already know it so well and know it's about bomb proof, especially like you said, with chromoly axles, which takes 10 minutes to swap in lol.
In the middle 80’s circle track racers embraced the 9” because of the drop out centers, racers could tune the rpm of the engine to the racetracks quickly. This was especially true of classes that were not allowed to use a quick change rearend.
Another great, informative video from UTG - now I want to go down the rabbit hole on IRS differentials and find out what their plusses and minuses are...
I like the dana 60 it held up great in my 1967 GTX 4-speed put the hammer down many times and changed a few clutches. I got fairly quick with that inland shifter
I have been beating on a 9 inch with stock shafts in my 6800lb cherokee. 37s, beadlocks, Detroit locker. It takes way more than it should. But it for sure drags. You can feel it. But I won't ever break the gear.. stock shafts eventually
I’ve always loved being able to take a pumpkin out of an eight three-quarter it’s the best
That was a very good technical presentation! Once again just a accurate assessment of pros and cons, with a interesting side of history. Bravo! You can tell I'm a dinosaur, I still use the old GM 12 bolt jackpot. The Pontiac-Olds that was top dog in the 60's, in most of your high horsepower classes. They were never plentiful or cheap, but if you were running a Chevy gasser, the only way to go. The Ford is the way to go now, given the market. Great lecture!
Another good thing about it is you can have multiple gear ratios in different carriers and depending on what you are doing you can swap it out. Put steep gears in depending on the track to get different results. Same with the Chrysler center you have there on the table.
So back in the day, the 9" Ford was designed primarily for the Lincoln. Think back seat in the Kennedy convertible. As close to zero drive shaft tunnel as possible.
2 piece drive shaft where the slope was in the front half and the back half was flat under the floor w/ a very small tunnel.
I have always preferred the 8 3/4 Chrysler for bigger power and the 8" Ford for smaller power cars. Add a thread in brass rod in an 8" Ford that rides 0.010" off the side of the ring gear opposite the pinion engagement and it's pretty darn beefy. If you are over 400 HP and have enough tire to mean something, 8 3/4 all the way. Either is more efficient than a 9" 🙃
really,the only weakness of the 8 3/4 is the housing will flex. welding on a back brace solves that problem; but you probably know that.
Tony, thanks for the history lesson.
AAAAA+++++++ I highly recommend your channel to all my geared friends.
This tutorial is priceless!👍
Off topic here. DDs speed shop has talked about taking a Chevy Nomad on the power tour, not the Uncle Tony charger. Has your plans changed on the project since it may not be taking a long drive in the summer?
I wanted to put a Ford 9" in my P3 - Permanent Pacer Project - but I'm currently rocking a Ford 8.8" - because a 9" Simply Won't Fit. Equipped w/a torque-biasing diff, backing up an LS3/5L50E combination, it's more than entertaining enough in the very SWB Pacer.
hello from Australia UTG ,greatest auto channel on youtube , i have a 351W up front followed by a top loader and i really wanted a 9 inch LSD in back and get rid off that single spinning Falcon diff before it lets go ,i purchased a 9 LSD and paid a mechanic to fit it as i had just gone through a herniated disc and needed to do physio ,dropped off in morning and picked up in the afternoon and it was awful ,everytime i made a sharpish turn in 1st or 2nd one wheel would almost stop turning and churp churp especially around a roundabout ,i took it back and the mechanic said thats how it should be ,thats BS all i wanted was two wheels to spin ,how can i stop this wheel doing this as i made a bit of a goose of myself and the mechanic barred me from hes workshop
i remember when we had about 20 ford 9inch rear ends laying everywhere we swapped our fuel altered to a bullet proof 9 inch had one think it was from a bronco it fit perfect in an s10 you could buy mini spools for dirt cheap instead of welding spider gears. thos were the days
Loved the video. I own two of those Ford 9-inches in running cars.
Stock, the 9" isn't particularly strong.
It's the aftermarket that makes it great combined with the removable centre, which means it's so damn convenient. Because it is so well supported in the aftermarket, parts are relatively cheap and available.
Great video, I love my 8.8 in my 85 mustang. It works great for my use.
yeah they are cheap and plentiful!
Had the 9" in my 72 Grand Torino Sport Fastback with the Cleveland, trucks, & T Birds 76 thru 78)4 of them/racing & street. The Torino 9" was used up so I took one out of a Police car a guy had in his salvage yard. It was a 2:50:1 ratio. That Torino then had some long highway legs for fast cruising without high RPM. And those 9" rears held up plus easy to work on. P.S. They need to raise the ground clearance on cars cause our roads are crap. Every entrance into or out of a business in town has right at a 45 degree v notch from the street to the driveways or parking lots. Everywhere you see gouging in the pavement because of this & damage to the cars. Plus thousands of miles of gravel roads throughout the State.
Awesome video Uncle Tony. One thing I did not know until recently is when you purchase a brand new 9 inch these days more often than not they will be noisy because of how modern gears are machined.
A proper street gear set up should be quiet,ish. Racegear set up will always be noisy,, set up for performance not to be quiet.
As always, Uncle Tony, I learned a ton from this video! In fact, it made me think of "Sarah-N-Tune" who's stuffing a Toyota V8 in a Corolla and what Toyota transmission and rear axle she could use to make all work out. I guess I'd appreciate more reasons why you'd want a Ford over a GM over a Mopar over a Dana over a etc.
I've busted the pinion/ring gear on a Chevy 10 bolt, did it again on a Dana 44 in a CJ5, had the spider gear retainer pin slip out and hit the pinion on a Dana 60 locking it up on me, full floater, so I pulled the axles and towed it home.
I love 8- 3/4s! I have an 1980 D150 with the 9- 1/4inch with 2.76 .Like a GM it has the C-locks holding the axle in. They are sloppy with only 100k miles and my fingers are crossed. I tried switching the axle and spiders to new parts with no uptake in the slop. I am looking for a 72-74 D100 junker with an 8 3/4 housing.I like the old Timken tapered roller bearings with adjuters by shim on 64 and older or threaded doohickey on the right side 65 on up. My buddy had a hot 62 Chevy pickup and got on it hard and a c-lock jumped out and the axle came loose and wiped out his new purple metalflake paint job on the left side of the bed. I am not enamored of any Mopar rear ends witha tin bolt on cover.
We used the Chrysler for years, it lets you out the motor up a little higher in the chassis with out so much tilt. It’s plenty strong as long as you don’t get into tire shake
Gott love uncle Tony! Looks like a retired hells angel, sounds like he designs for n.a.s.a. friggin love this guy!
Love the gusseted 8.8 I put in my camaro.
I have a question about an 8.8 rear dif from a 04 Cobra It only has 25000 miles but I had to replace the crush sleeve and the pinion flange Did not get The reading on the rotational resistance before I took it apart. I have it in between the spec that Ford recommends for the preload 8 to 14 around 10 or 12 Ib-in for me. Everything feels smooth when I rotate it And I used gear marking compound To see the pattern at least. My question is with such low miles should I expect a wining noise from having reset the preload and not knowing what the previous spec was. And what might be a way to go about Getting it to stop. Thanks man also always find your videos super helpful And I end up learning a lot every time keep up the great work👍👍
Crush sleeves don't go bad unless excessive wheel hop occurs or no mercy reverseis ,neutral drop on TH-cam ifn u don't kno what dat is, both are driver error unless a mechanic over tightened the pinion nut after a seal change
I have a 8 1/4 with 3.91 limited slip in my 360 Duster A-500
I always learn something from watching your videos thanks Tony
The 9 inch Ford really came into prominence NOT in NHRA and drag racing but through those good old boys down South.....NASCAR. When the roundy round boys figured out that they could make a full floater rear end out of these things and then discovered rear end coolers they became mandatory if you turned left. They are still used in a LOT of circle track cars due to strength, gear ratios and many other reasons. They are MUCH easier to set up than a 12 inch chevy and more durable.
Well hell, Now I want you to go deep on the Dana 60. Pros and cons. Where does it get its legendary strength? Where was it popular in racing? I get so much out of these vids where you nerd out and a specific component. U joints sizes and strengths and driveshafts materials balancing yoke sizes.
In Trans Am Javelin we had AMC Salisbury style rear end, Hotchkiss makes gear swaps much easier,(we usually changed complete rear end) but out on the course Salisbury is measurably more efficient and runs cooler but both required coolers
@UncleTony What about the FORD 9 3/4 inch behemouth under my truck????
Great info, thanks!
I always thought of jungle Jim and Vega funny car it had a raced out bbc but he switched to mopar hemi ……such a rad era of drag racing 🤯
Hey uncle Tony, we appreciate you much! my 68' Fairlane 500 fastback has the 8in rear differential. originally came with 302. im installing a 390 and was thinking of a 9in swap but after watching this im not sure..