[tsc1969]

Does anyone have information on the maintenance intervals for the transfer case and rear differential?
How about refill capacities?
All I can seem to find is information on where the drain plugs are and which gear oil to use.
Thanks,
Tim C.

 

[XRDreamliner]

Does anyone have information on the maintenance intervals for the transfer case and rear differential?
How about refill capacities? All I can seem to find is information on where the drain plugs are and which gear oil to use.
Thanks,
Tim C.

100k miles for "Normal" service, 50K miles for "Severe" service; FWIW, I don't pull a trailer, or operate typically above 90 deg F - some factors that make it "severe" service, however, I changed the rear diff and transfer case fluids @ 40k miles. The rear diff fluid was black, and the magnet had a good amount of black sludge on it. Conversely, the transfer case fluid was still honey colored, with an almost clean drain plug magnet.

Both rear diff and transfer case take 0.88 liters of fluid each. After you drain the fluid (hot), refill through the fill plug until the fluid seeps out the bottom of the fill plug threads.

 

[tsc1969]

Thanks yery much. That was exactly the information I was looking for.
Tim C.

 

[XRDreamliner]

To make the job easier, buy a $6 dollar manual pump that screws onto the gear oil bottle. It makes filling the rear diff and transfer case much easier.

Oh, and I used GM Hypoid 75W-90 as the replacement fluid - GM added a grape scent to cover the sulfur smell :thumb:

 

[tsc1969]

To make the job easier, buy a $6 dollar manual pump that screws onto the gear oil bottle. It makes filling the rear diff and transfer case much easier.

Oh, and I used GM Hypoid 75W-90 as the replacement fluid - GM added a grape scent to cover the sulfur smell :thumb:

Great idea on the pump. Have to look into that.
I'm surprised they would add a scent to the gear oil. That's the first I have heard of it.
Thanks,
Tim

 

[medicrxdoc]

The added scent does lighten the wallet a little though. Gmpartsdirect.com doesn't ship it due to spillage. Dealer prices vary, but is was too expensive for me. Got gallons for the price of a few dealer quarts would have cost.

 

[XRDreamliner]

The added scent does lighten the wallet a little though. Gmpartsdirect.com doesn't ship it due to spillage. Dealer prices vary, but is was too expensive for me. Got gallons for the price of a few dealer quarts would have cost.

gmpartsgiant will ship it to you:

http://www.gmpartsgiant.com/parts/gm-lubricant-89021677.html

$60 for 2 bottles shipped to my door. I used GM fluid because I'm still under Powertrain Warranty, so if I had issues with my transfer case or rear differential carrier, then using the GM fluid (vs. other brands) would not factor into the warranty discussion.

 

[bigblumer]

I just replaced the transfer case and differential fluids in my Outlook. I splurged and used Amsoil Severe Gear, I'm not an Amsoil guy, as I like to change my oil often and anything rated to go 25,000 miles would just be a waste. But I figured, "Why not", since it may be another 5 years before the fluid is changed again.

The rear differential is easy as pie. It only took a few minutes to drain and refill. The front transfer case is a different story. The fill plug is tucked up above the exhaust, and my 10mm Hex socket just wasn't long enough. I was able to custom make a part out of an alan wrench and a ratcheting closed-end wrench, but it was a pain.

The rear fluid was dark black/gray with lots of gunk on the magnet, which sounds pretty typical for this vehicle. The front transfer was dark, but not like the rear.

However, in the end it was all worth it. I was able to replace all of the fluids for less than 30.00, and an hour of my time. I think the dealer price is 250.00 or something outrageous. Next time, it will definitely take me less time, now that I have fashioned my own custom part.

 

[tsc1969]

Thanks for the info!!!
Bought the gear oil last week and hope to do it this weekend.
Tim

 

[glbbrown]

Looking for the location of the transfer case drain and refill plugs. Pictures or diagrams would be helpful. All I hear is it is above the exhaust manifold....

 

[tsc1969]

Looking for the location of the transfer case drain and refill plugs. Pictures or diagrams would be helpful. All I hear is it is above the exhaust manifold....

Drain and fill plugs are on the passenger side of the transfer case. The fill plug is behind a sheet metal heat shield and can be accessed from above the exhaust pipe. I used an allen socket and extension on a ratchet to reach it. I also removed the heat shield for easier access.
I tried attaching diagrams but this site wouldn't allow the files to upload.
Tim C