Differentail

[Cobra]

Wanting to change Differentail fluid. Just bought 3 quarts of Royal Purple, gasket, red rtv, and brake cleaner. ANything else I need before I begin or anything I should do while I'm in there?

 

[NathanJax]

I'm AWD...

I did both front and rear diffs, and the transfer case at the last time (about 2 weeks ago). Used 2qts of Royal Purple Synchromax for the transfer case, and almost 2qts in my front diff and just over 2qts in my rear diif of Royal Purple Gear Fluid.

I bought a new gasket for $4 at Napa. We had gasket sealer, brake cleaner, etc. because we did it at my fathers shop.

 

[destroyer1362]

not to thread jack, but does the color of the rtv matter? is there a difference?

 

[pittmanb8]

Just did my 3 fluid changes this weekend- front and rear differential plus transfer case. About 2 qts in the front and 2.25 in the rear. About 1.75 qts in the transfer case.

For the rear differential, have a long wrench on hand to break the fill plug- it is usually tough to get out.

Also, for the rear differential and transfer case, you should use thread sealant on the plugs. For the front differential it is not needed since it has bolts with plastic washers.

I would suggest against RTV on the gasket, it will work just fine with a good quality gasket like fel-pro. Do make sure that you have a steel brush and razor blade on hand to clean off the old gasket.

 

[Cobra]

not to thread jack, but does the color of the rtv matter? is there a difference?

Thats what the guy at Autozone gave me. I believe it is high temp.


When you guys are saying the front is that cuz you guys have 4 wheel drive? I was just doing the rear. My hoe is just 2 wheel drive ...uhh... maybe I should go look under my Tahoe before I post this.

Also what is a transfer case?

 

[NathanJax]

Thats what the guy at Autozone gave me. I believe it is high temp.


When you guys are saying the front is that cuz you guys have 4 wheel drive? I was just doing the rear. My hoe is just 2 wheel drive ...uhh... maybe I should go look under my Tahoe before I post this.

Also what is a transfer case?

Hahaha....

Yeah, it's for those of us with 4 wheel drive or all Wheel drive. You with 2 wheel drive, only need to worry about the rear...

Transfer case is for us that are 4WD or AWD and it transfers the power to the front and rear (AWD or 4WD) instead of just the rear (2WD)

 

[unixadm]

You'll need around 2.5 quarts. Take the gear oil and put it in the sun or a sink full of hot water for a while. It will make it much easier to fill the diff, along with a small piece of hose if you don't have a fluid pumper. Also check the bottom of the differential to see if it has a drain plug. I know on my Yukon XL, there is a drain plug that looks just like the fill plug in the bottom of the case. Tech at dealer said the XL's and Suburbans had plugs, but hey it's worth a look. That can save you some work if you don't want to pull the cover. Secondly I do not use RTV on rear differentials. If you clean the surface properly with a scraper and install a new gasket, I've never had one leak. I usually use Ultra Black and if you do use RTV, just use a VERY small amount. Torque the bolts in a criss-cross pattern

 

[rigo_jones]

damn looks like i should do this too. i have no idea when the previous owner changed it.

 

[Robert.K]

how often does transfer and differential fluid need changing? and what is the brake cleaner for?

 

[Cobra]

Done! Not so bad. Put a very small bead of RTV. CLeaning the old gaskets off with a razor blade seemed to have taken the longest. But did my best to get it as smooth and clean as possible. I had no drain hole. Also there was magnet on the pay to catch any shavings. I may have put more that the 2 & 2/3 bottles of Royal Purple but kept checking for fluid. Either way also did the motor oil change. Took it for a test drive and running good and smooth. No unusual noise or feeling. Now I need to do the Tranny with RP.

Brake cleaner I used to clean the pan and sprayed the differential out get all the crap out. The fluid & the gears did not look bad but, on the pan around the magnet I could see build up of mettalic funk. Got it all clean now.