Differential Oil Change Tip
Thread Starter
SUBVETTE
Joined: Jul 2006
Posts: 3,841
Likes: 93
From: San Diego CA
Differential Oil Change Tip
Changed my Diff oil yesterday and wanted to pass on a tip for anyone else doing the job. The job was a breeze because I went down to Harbor Freight and bought a small hand operated transfer pump ($3.99) which comes with plastic inlet and outlet tubing that each are about 24" long. This allows you to put one hose into the hard to reach fill port, the other hose into the Dexron 75W-90 oil container a couple of feet away and pump away while sitting on the garage floor, instead of trying to get a container with a hose on it up by the differential fill port while lying on your back trying not to spill it on yourself. Makes this job a piece of cake. 
Burning Brakes
Joined: Mar 2010
Posts: 1,047
Likes: 0
From: Warwick NY
Question. I have had many high performance street cars and have never changed the rear end oil unless for a gear change. Never had a problem and I don't baby them. Do these cars really need to change out the oil because of the design or just another money making GM deal. Figuring the customer will bring them back to the dealer?
Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
Question. I have had many high performance street cars and have never changed the rear end oil unless for a gear change. Never had a problem and I don't baby them. Do these cars really need to change out the oil because of the design or just another money making GM deal. Figuring the customer will bring them back to the dealer?
IMO it's very cheap insurance.
Drifting
Joined: Sep 2000
Posts: 1,456
Likes: 5
From: Bothell WA
If I remember right, the owner's manual recommends that the diff fluid be changed after a cumulative 24 hours of autocrossing or HPDE activity. That's probably because of the heat that gets generated in the diff under those conditions breaks down the fluid. So I change mine every couple of years since I'm only occasionally at the track. I do it myself, so the only cost is the new gear lube. If you only run your car on the street, I wouldn't worry about it.
- Mark
Thread Starter
SUBVETTE
Joined: Jul 2006
Posts: 3,841
Likes: 93
From: San Diego CA
Mine was starting to get a little noisy sometimes on tight turns (clutches sticking) and the last time it was changed it was before the latest Dexron 75W-90 fluid was recommended by GM. Mine had the previous generation oil with separate friction modifier added, so I figured it was time to get the newer stuff put in.
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Burning Brakes
Joined: Jun 2007
Posts: 877
Likes: 142
From: Little Egypt, USA
Mine was starting to get a little noisy sometimes on tight turns (clutches sticking) and the last time it was changed it was before the latest Dexron 75W-90 fluid was recommended by GM. Mine had the previous generation oil with separate friction modifier added, so I figured it was time to get the newer stuff put in.
Good move changing to the new oil, smooth as silk.
Burning Brakes
Joined: Jun 2005
Posts: 913
Likes: 129
From: Toronto
Thread Starter
SUBVETTE
Joined: Jul 2006
Posts: 3,841
Likes: 93
From: San Diego CA
Burning Brakes
Joined: Jun 2007
Posts: 877
Likes: 142
From: Little Egypt, USA
I've been using a marine lower unit lube pump from Walmart that screws on to a quart bottle that pumps with your thumb. Slow and needs to be close but it works.
Tolero Apto Victum
Joined: Jul 2007
Posts: 9,669
Likes: 37
From: Woodlands TX
Question. I have had many high performance street cars and have never changed the rear end oil unless for a gear change. Never had a problem and I don't baby them. Do these cars really need to change out the oil because of the design or just another money making GM deal. Figuring the customer will bring them back to the dealer?
