4x4 Maintenance

As I mentioned in another post my dealership suggested a fluid change on front and back differentials and transfer case. Seems easy enough since the front diff and transfer case have drain plugs. Looks like the biggest pain is dropping the spare tire to get access to the rear diff bolts haha

Has anyone put an aftermarket rear diff cover with drain plug to help with the next service since you have to remove it?

Any fluid type recommendations besides the GM fluid from the dealership?

It’s a 6.2 8 speed 4x4 are the fluids and rear diff gasket the same as the 5.3?

6.2 8 speed, you must be in the wrong generation forum…all the 2021+ units have a 10spd.

Yes, I’d recommend changing front and rear diff and transfer case every 45k miles, along with the transmission.

Crap. Didn’t realize I was in the wrong section. Hopefully a moderator can move this to the 2015-2020 section. Thanks.

Jake707 said:

As I mentioned in another post my dealership suggested a fluid change on front and back differentials and transfer case. Seems easy enough since the front diff and transfer case have drain plugs. Looks like the biggest pain is dropping the spare tire to get access to the rear diff bolts haha

Has anyone put an aftermarket rear diff cover with drain plug to help with the next service since you have to remove it?

Any fluid type recommendations besides the GM fluid from the dealership?

It’s a 6.2 8 speed 4x4 are the fluids and rear diff gasket the same as the 5.3?

Click to expand...

Rear diff on the 6.2 is different from the 5.3. Make sure you buy the correct gasket. I replaced the diff and T-case fluids on my '17 6.2. Easy, you shouldn't have any issues.

No need for fancy fluids......mostly just what your preference is. I tend to use full synthetic front and rear, OEM stuff is good too. Transfer case should be Dexron 6. If you have an extractor with the stiff hose, you can suck out the rear diff when it's warm and replace with new. It's not 100%, but it refreshes it without the hassle of the rear cover and gasket. I do wish they came with a drain plug like the old days....

Yeah that damn 6.2 rear dif cover was kind of a PITA to remove and replace - I had to pull the panhard bar to get it off and on. I had my eye on a Yukon cover on AMZ but it was for a 5.3 drivetrain. Cheap would be to drill a hole and add a helicoil with a plug. The only thing is its not needed too often like an oil change - maybe every 3 years - so dropping a few hundy isnt really cost effective...

I run Amsoil in all my differentials. The squeeze pouches are super easy and when there’s a sale or deal, it’s around the same cost as OEM fluids. Like what was mentioned above, if you have a fluid extractor, you can pump out the rear diff and refill. If the cover has already been removed and the diff/cover wiped clean in the past, then there shouldn’t be many metal particles in the diff. Your call. There are many people out there who never service any of their differentials, so though it’s not as thorough as removing the cover, a drain and fill is much better than nothing.

I ended up ordering the AC Delco fluids for all 3 holes and was able to knock this out Sunday, even got the wife and daughters under there to "help" haha.
Since my street is a slight hill I pulled it up on paver strips I have on the side yard that I did for the boat a few years ago and laid a blanket over the grass. My youngest thought it was a dam picnic and started bring dolls outside to hangout under the yukon haha.

The job overall is super easy and if the spare tire wasnt there the overall time would have been cut in half since it blocks straight access to the top half of the rear diff cover and I couldnt use my impact to zap off the bolts. I kept the tire there instead of dropping it since I figured the time to drop it out of the way would take just as long as the time to just work around it.

I think I was into it ~$200 for all the fluids, gasket and bottle pump tool plus I got my girls active turning the wrenches so Id say a win for me

Good for you letting the family help! I really need to do better with that. I have very little time so I always end up rushing and then get frustrated and then they do not want to help me anymore lol. I need to learn to relax and know it WILL take longer but try and let them help more.

Nice job doing it yourself though! I took the same path on mine and left the tire on and worked around it but got it done relatively painlessly.