for 2020 wrx owners, Subaru changed both drug and fill plugs go on the rear diff. transmission into H10(drain) & 17mm(fill). fyi, both relocated from back side to passenger side.
Thanks for your very descriptive DYI. Also, for the very sincere encouragement for those people who's afraid to do their own car maintenance. I also started that way. We need that sometimes... God bless you brother.
Hey man, thanks for the very detailed and informative video. I have a ‘13, but looking at other videos everything is very similar and the process is the same. Gonna be trying it soon. The pump for the rear diff is awesome, hopefully all goes smoothly!
Interesting jack stand locations on the front... why not on the pinch welds as marked in the manual? Also shouldnt the car all be jacked up at once so its level when draining and adding fluids?
...hardest part for me is putting the new fluid in through the dipstick hole. I didn't have a long reach funnel or an adapter and long hose. I have a fluid pump, but it was really awkward under the car. I ended up pouring by hand into a double funnel setup. It took me 10-12 minutes to pour 1 bottle so I didn't overwhelm the funnel(s). Find a long hose funnel and it will go easier.
@@K03sport I’m over 40k and haven’t done it yet. I had clutch/trans work and had metal in trans/front diff so I’m pretty sure dealer did that. I’m probably gonna have a local shop do the rear diff and brake flush in spring time
Great video. Does having the front end higher in the air prevent all the fluid from draining out? And then after filling it, is the measurement on the dipstick accurate when it is not level? I'm trying to decide if I need to get the whole car on stands or not.
If you have the ability to raise the entire car evenly, do that. However.. I dont think the added angle on the car makes enough of a difference when filling/draining. As long as you're not underfilling..
I made the mistake of going for a top mount intercooler that makes it a complete pain to get to top of transmission, brake fluid, clutch fluid tanks and low pressure air conditioning valve. Getting the T-70 off took us a ton of effort, couldn't brake it free with a meter long torque wrench or gun for a very long time... eventually managed it but it was bizarrely tight. We think we caused a failure in the transmission case halves gasket.. slow leak now thats a pain in the ass to top up.
Just did my first fluid replacement, thanks for the guide. I ended up using the Subaru 75W90 fluid though. Any particular reason to go Motul over subaru? Better if you're racing I guess? I am not racing, just occasionally spirited daily driving.
Note that the Subaru WRX service manual says to replace the crush washer on the transmission drain plug. You said in the video that the gasket is re-usable but that's not correct.
The washer on the trans plug isn't a standard "crush washer" it's just a standard washer. I've reused it twice now and haven't had a single instance of leaking.
@@WRXGarage While good practice dictates replacing crush/sealing washers, I reuse them all the time too. The only time I had a problem, the issue was quickly fixed but slightly loosening the drain bolt and retightening to the proper torque.
it's a few dollars. they say to reuse it to rule out the possibility of a leak. if you trust the old washer, use it. if you want piece of mind, buy a new washer (or 2)and have them on hand.
Shouldn't put the diff top plug in if it has oil running out. That is too full. Gail Banks found that over filling a diff, even just a little will cause it to run too hot.
Honestly, most people don't torque their spark plugs as it's terribly difficult to get a torque wrench into that spot. Just do NOT over tighten them. The spec is like 15ftlb
finger tighten all the way (to avoid cross threading) , then give a nudge at the end w/the socket. You're just making sure that the plug is seated firmly.
where did you put the jack stands? it looks like the fronts are on the cross-member brace nearest the LCA bolt; is that a solid load location? Did you do front first then rear, or rear first then front, or one side then the other side? was the car level when you did the trans?
Yes, the bolt on the LCA is a jack point because it puts the weight onto the frame. I jack the car up using the pinch welds and because the jack takes too much room, I put the stands on the LCA bolts. For the rear, you can just jack the rear diff and put the stands on the pinch welds on each side.
@@WRXGarage I use the front central lift point (just aft of the oil drain) and put jackstands at each of the pinchwelds. Because my long frame floor jack is too thick to slide under the front of the wrx, I drive up on a short length of 2x10 under the front wheels which gives just enough clearance to slide my floor jack underneath. I then lift on the rear diff and put 2 more jackstands under the rear pinchwelds to get the car elevated and level. That gives me plenty of room to safely work underneath the wrx.
@@K03sport Yeah I wanted to go that route too thinking it was OEM stuff, but a Subaru shop manager told me it's just generic oil made and bottled at a nearby plant... lol
@@WRXGarage I saw that it says it "detracts from driveability and fuel mileage" in the manual. I changed with 75w90 today but I'm uncertain now. Love the videos by the way!
the 90 will be more friendly when warm. I can tell you that at 10*F, the tranmission shifts like pancake syrup in the fridge; definitely needs more effort. the water is 75w-90 is more popular and it is what is at the Subaru parts counter, ~$13 ish and change per qt.
Because of where the drain plug is, it's better to fill it when level, yes. As long as its not angled downwards in the back, that would lead to underfilling.
@@WRXGarageThanks I did it last time from this video, but on a lift. Just wanted to make sure so I can do it on stands this time if need be. Thanks for the quick response!!
@@WRXGarage Cool, great info in case I can’t get on the lift. What about the transmission? Did you drop it back down to fill the front or just do 3.3 liters?
as fast wrx says, some STi ppl like the feel of the LS fluid in the rear diff. read your owners manual and see what fluid is spec'd. Worst case, email fastwrx and see what they say. Dan is pretty good at replying w/in a day or 2...
Hello, anyone here has experienced engine light codes P0018 and P0021? I got this two on my 2019 Wrx stage 2. The car drives fine, no issues, no mechanical issues. I just dont know what this error is, car only has 9000 miles on it and oil always changed. Thanks
It’s probably the Oil Control valves and Cam Gears or maybe faulty sensors. I have the P0016 code and the dealership said the car is fine. The code still bothers me tho
Thanks bro really helpful video. But my concern is there’s no front differential because I went to the dealer and they are trying to charge me $500 for changing rear and front differential fluid.
Love the channel. But like I tell everyone, never race a vehicle on on anything stock. I've got a '16 wrx and would never stress it unless fully built. Especially hope u have a built trans as well as built motor. Suspension, braking? Gonna cost u $15k to race with confidence
@@WRXGarage your basically a trans away from an sti. Not a huge fan of the ej vs the fa gen for making power to a certain point. I think the lawsuit filed against subaru specifically listing the ej as a know defective motor (ie ringlands) probably contributed to the sti's demise. It's up to enthusiasts to cobble together their own stis now
@@WRXGarage man i wanna buy an STI with a broken motor and mount a properly built FA in there that would be quite the build. shame subaru quit making the STi, i had my hopes up they were gonna make an FA engine STi.
Overfilled diff is always going to be safer than underfilling. The way the diff is designed, its impossible to overfill it to an extreme extent, even with the car raised in the rear. we're talking about maybe 5-10% more fluid which again is way safer than 5-10% less fluid.
for 2020 wrx owners, Subaru changed both drug and fill plugs go on the rear diff. transmission into H10(drain) & 17mm(fill). fyi, both relocated from back side to passenger side.
Much appreciated my dude
Thank you so much. I got under my car and was like wtf.
Thanks for your very descriptive DYI. Also, for the very sincere encouragement for those people who's afraid to do their own car maintenance. I also started that way. We need that sometimes... God bless you brother.
Hey man, thanks for the very detailed and informative video. I have a ‘13, but looking at other videos everything is very similar and the process is the same. Gonna be trying it soon. The pump for the rear diff is awesome, hopefully all goes smoothly!
Interesting jack stand locations on the front... why not on the pinch welds as marked in the manual? Also shouldnt the car all be jacked up at once so its level when draining and adding fluids?
Thanks so much for this guide, I just bought a WRX and am hoping to change the trans fluid and differential fluids so I appreciate this video
...hardest part for me is putting the new fluid in through the dipstick hole. I didn't have a long reach funnel or an adapter and long hose. I have a fluid pump, but it was really awkward under the car. I ended up pouring by hand into a double funnel setup. It took me 10-12 minutes to pour 1 bottle so I didn't overwhelm the funnel(s). Find a long hose funnel and it will go easier.
appreciate the solid tutorial man! great guide!
you just gained a subscriber thank you
Great video! I plan on doing this to my 2019 wrx soon!
Thanks for the amazing video! Will definitely save this for my 30k service for my wrx. I'm around 20500k ish.
I did my at 60k mi (oops). everything seems fine and the fluid was the same color. I did my rear did at 55k miles (Oops again)....
@@K03sport I’m over 40k and haven’t done it yet. I had clutch/trans work and had metal in trans/front diff so I’m pretty sure dealer did that. I’m probably gonna have a local shop do the rear diff and brake flush in spring time
Great video. Does having the front end higher in the air prevent all the fluid from draining out? And then after filling it, is the measurement on the dipstick accurate when it is not level? I'm trying to decide if I need to get the whole car on stands or not.
If you have the ability to raise the entire car evenly, do that. However.. I dont think the added angle on the car makes enough of a difference when filling/draining. As long as you're not underfilling..
I made the mistake of going for a top mount intercooler that makes it a complete pain to get to top of transmission, brake fluid, clutch fluid tanks and low pressure air conditioning valve. Getting the T-70 off took us a ton of effort, couldn't brake it free with a meter long torque wrench or gun for a very long time... eventually managed it but it was bizarrely tight. We think we caused a failure in the transmission case halves gasket.. slow leak now thats a pain in the ass to top up.
Awesome video. Thank you bro!!
Great job.
Sorry for asking but is that manual or auto trans?
Manual!
Just did my first fluid replacement, thanks for the guide. I ended up using the Subaru 75W90 fluid though. Any particular reason to go Motul over subaru? Better if you're racing I guess? I am not racing, just occasionally spirited daily driving.
Getting prepped for some racing!
Yessir!!
Great video! Can I use the Motul 90PA fluid for the rear differential?
amazing walk through!!
Where did you find the Motul gear 300 fluid? I’ve been having a hard time finding it. Appreciate the info. Thanks
import image racing
@@jacklin9768 it’s sold out there as well
Note that the Subaru WRX service manual says to replace the crush washer on the transmission drain plug. You said in the video that the gasket is re-usable but that's not correct.
The washer on the trans plug isn't a standard "crush washer" it's just a standard washer. I've reused it twice now and haven't had a single instance of leaking.
@@WRXGarage
While good practice dictates replacing crush/sealing washers, I reuse them all the time too. The only time I had a problem, the issue was quickly fixed but slightly loosening the drain bolt and retightening to the proper torque.
it's a few dollars. they say to reuse it to rule out the possibility of a leak. if you trust the old washer, use it. if you want piece of mind, buy a new washer (or 2)and have them on hand.
What a valuable video and patreon!
🙌🙌🙌
@@WRXGarage I joined! My 1st oil change would've gone smoother with the knowledge I have now.
Thanks for the support man ❤️
Good thing you got your eyebrows done before the video bro 😂😅
what does this even mean?? lol
So just 1l to do rear differential correct
For wrx 2006 is the same no ??
Shouldn't put the diff top plug in if it has oil running out. That is too full. Gail Banks found that over filling a diff, even just a little will cause it to run too hot.
what happens if you tighten the bolts too much? does it impact anything?
They will seize and you'll have to replace the entire transmission. Or weld on a new bung which is expensive
Where exactly are you putting the jack stands under the car if you jack it up from the jack points on the front side jack points?
Jack stands are going onto the bolt where the lower control arms connect to the frame!
How important is the torque specs? I have been ready to take on this and spark plugs but gathering parts/ tools I need
Honestly, most people don't torque their spark plugs as it's terribly difficult to get a torque wrench into that spot. Just do NOT over tighten them. The spec is like 15ftlb
@@WRXGarage
Actually closer to 13 lb ft.
finger tighten all the way (to avoid cross threading) , then give a nudge at the end w/the socket. You're just making sure that the plug is seated firmly.
where did you put the jack stands? it looks like the fronts are on the cross-member brace nearest the LCA bolt; is that a solid load location? Did you do front first then rear, or rear first then front, or one side then the other side? was the car level when you did the trans?
Yes, the bolt on the LCA is a jack point because it puts the weight onto the frame. I jack the car up using the pinch welds and because the jack takes too much room, I put the stands on the LCA bolts. For the rear, you can just jack the rear diff and put the stands on the pinch welds on each side.
@@WRXGarage
I use the front central lift point (just aft of the oil drain) and put jackstands at each of the pinchwelds. Because my long frame floor jack is too thick to slide under the front of the wrx, I drive up on a short length of 2x10 under the front wheels which gives just enough clearance to slide my floor jack underneath.
I then lift on the rear diff and put 2 more jackstands under the rear pinchwelds to get the car elevated and level. That gives me plenty of room to safely work underneath the wrx.
What impact driver do you use?
1/2" Milwaukee, and a 1/4" DeWalt for the smaller stuff
Do you have mt tranny fluid change video?
Can someone explain why every wrx channel is using this oil? From the testing I've seen it's mid-tier at best?
🤷♂️ Motul has always been closely related to Subaru's. Most tuners recommend it and I've run it in my diff and transmission for 60k miles.
I just used Subaru stuff (white bottle) and it was less than $14/bottle. same price as IIR and I don't have to wait or pay shipping....
@@K03sport Yeah I wanted to go that route too thinking it was OEM stuff, but a Subaru shop manager told me it's just generic oil made and bottled at a nearby plant... lol
quick question. What brand and specs is the torq wrench..been trying to find one but dont know to much about them..size wise
It's a Tack Life 1/2" torque wrench, idk if they even sell them on Amazon anymore. It's off-brand but it's held up for 4 years now without any issues
@@WRXGarage thanks i think harbor has that one as well
Harbor freight is also a great option! Definitely look at buying a set of cheap adapters so you can use 3/8 sockets on it too
What torque wrench are you using
Tacklife 1/2" torque wrench. Can't find the exact model in Amazon anymore, here's the closest one, pretty much the same exact design. amzn.to/3CWB8RI
Thank you for this video, sir! Super helpful.
Absolutely!
Is there any difference in using 75w90 vs the factory fill 75w80?
75w90 is the spec listed in the maintenance manual.
@@WRXGarage I saw that it says it "detracts from driveability and fuel mileage" in the manual. I changed with 75w90 today but I'm uncertain now. Love the videos by the way!
I've been running 75w90 for 4 years and haven't noticed any issues. It'll definitely be better long term for reliability
the 90 will be more friendly when warm. I can tell you that at 10*F, the tranmission shifts like pancake syrup in the fridge; definitely needs more effort. the water is 75w-90 is more popular and it is what is at the Subaru parts counter, ~$13 ish and change per qt.
Does the car need to be level to do the rear differential?
Because of where the drain plug is, it's better to fill it when level, yes. As long as its not angled downwards in the back, that would lead to underfilling.
@@WRXGarageThanks I did it last time from this video, but on a lift. Just wanted to make sure so I can do it on stands this time if need be. Thanks for the quick response!!
Even if you raise the rear, but the fronts are on the ground, you'll just end up overfilling the diff by a tiny bit, which is totally fine.
@@WRXGarage Cool, great info in case I can’t get on the lift. What about the transmission? Did you drop it back down to fill the front or just do 3.3 liters?
Do you know the difference between the 75W90 & the 75W90 LS + 90PA? I seen on fastwrx they have multiple kits.
The LS kit is for limited slip differentials like a Cusco rear diff. I don't think the stock WRX or stock STI would use that kind of fluid.
Im looking at that right now actually and trying to figure out the same thing.
as fast wrx says, some STi ppl like the feel of the LS fluid in the rear diff. read your owners manual and see what fluid is spec'd. Worst case, email fastwrx and see what they say. Dan is pretty good at replying w/in a day or 2...
I couldnt get my diff drain plug loose, ended up having to siphon it out.
Hello, anyone here has experienced engine light codes P0018 and P0021? I got this two on my 2019 Wrx stage 2. The car drives fine, no issues, no mechanical issues. I just dont know what this error is, car only has 9000 miles on it and oil always changed. Thanks
It’s probably the Oil Control valves and Cam Gears or maybe faulty sensors. I have the P0016 code and the dealership said the car is fine. The code still bothers me tho
Thanks bro really helpful video. But my concern is there’s no front differential because I went to the dealer and they are trying to charge me $500 for changing rear and front differential fluid.
The front differential is built into the transmission!
So you’re also changing front diff fluid when changing trans fluid??? Great video btw!
Yes correct!! The rear differential is separate
@@WRXGarage do you recall if the fill and drain plug for the rear diff have crush washers???? If so do you have part#???? Thanks!
@@jericopaule8365 They do not, just the two plugs.
51.6 ft lbs for the transmission drain plug? I thought it was 32 ft lbs?
I've read 18 ft lbs lmfao
@@youtubeadmin3158 that's a new one lol
It depends on what washer your using. The black one oem part number 803926090 is ~51
How often should I change the transmission/differential fluid my subie current has 37k
I do it once every 18months! Every 15-20k miles
called subaru and they said 60k was the service miles ..they lied to me lol i called them at 28k to ask now im at 41k
Love the channel. But like I tell everyone, never race a vehicle on on anything stock. I've got a '16 wrx and would never stress it unless fully built. Especially hope u have a built trans as well as built motor. Suspension, braking? Gonna cost u $15k to race with confidence
just more reason to do an sti swap for the trans and maybe an aig block.
Time will tell 🤷♂️ already have full suspension, sway bars, endlinks, control arms, etc. Full Brembo swap brakes.
@@WRXGarage your basically a trans away from an sti. Not a huge fan of the ej vs the fa gen for making power to a certain point. I think the lawsuit filed against subaru specifically listing the ej as a know defective motor (ie ringlands) probably contributed to the sti's demise. It's up to enthusiasts to cobble together their own stis now
Yeah FA powered STI trans would be the dream
@@WRXGarage man i wanna buy an STI with a broken motor and mount a properly built FA in there that would be quite the build. shame subaru quit making the STi, i had my hopes up they were gonna make an FA engine STi.
Car is uneven surface. You will overfill your rear differential. Please dont do this guy. You need to jack all 4 sides and refill.
Overfilled diff is always going to be safer than underfilling. The way the diff is designed, its impossible to overfill it to an extreme extent, even with the car raised in the rear. we're talking about maybe 5-10% more fluid which again is way safer than 5-10% less fluid.
Rock climbing and subies 🫱🏾🫲🏼 good combo also amazing vid I’m about to change my fluids for first time this was very helpful
🙌🙌🙌