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.TSC1969 said: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.
Great idea on the pump. Have to look into that.XRDreamliner said: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:
gmpartsgiant will ship it to you:medicrxdoc said: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.
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.glbbrown said: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....