to me.
Differential Fluid
Thread Starter
Instructor
Joined: Jul 2005
Posts: 200
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Differential Fluid
The dealer is suggesting changing the rear end fluid with ATF. They claim this is the latest recommendation from GM in order to deal with noisy clutch packs. Any thoughts or suggestions?
Tech Contributor
Joined: Dec 2003
Posts: 19,384
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From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
Sounds like the latest "bring in some $$$ to the Dealer" scheme to me
The recommended fluids are:
Rear Axle Limited-Slip Differential: SAE 75W-90 Synthetic Axle Lubricant, GM P/N 12378261 (Canadian P/N 10953455) or equivalent meeting GM Specification 9986115. With a complete drain and refill add 118 ml (4 oz) of Limited-Slip Differential Lubricant Additive GM P/N 1052358 (Canadian P/N 992694) or equivalent
DEXRON®-III Automatic Transmission Fluid is the recommended lubricant for the Manual Transmission but the book says that manual transmission fluid doesn't require changing. Auto fluid change is changed at 50k if hot/hilly or high performance use or 100k for regular use.
Is your clutch particularly noisy?
The recommended fluids are:
Rear Axle Limited-Slip Differential: SAE 75W-90 Synthetic Axle Lubricant, GM P/N 12378261 (Canadian P/N 10953455) or equivalent meeting GM Specification 9986115. With a complete drain and refill add 118 ml (4 oz) of Limited-Slip Differential Lubricant Additive GM P/N 1052358 (Canadian P/N 992694) or equivalent
DEXRON®-III Automatic Transmission Fluid is the recommended lubricant for the Manual Transmission but the book says that manual transmission fluid doesn't require changing. Auto fluid change is changed at 50k if hot/hilly or high performance use or 100k for regular use.
Is your clutch particularly noisy?
Last edited by DeeGee; Apr 13, 2009 at 01:03 PM.
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From: Maker of Sharp Objects, AL - Roll Tide
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Royal Purple Max Gear 75w-90, or the Amsoil alternative :thumbs
Your dealer is trying to get business, thats all.
Your dealer is trying to get business, thats all.
Thread Starter
Instructor
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Just to clarify, it's time to change the rear end fluid anyway. I am just wondering whether using the "latest and greatest" from GM is the way to go. The cost is the same regardless of which fluid is used.
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I think I'd stick with the differential fluid. Perhaps one of the forum auto vendors could chime in on this supposed recommendation from GM.
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Tech Contributor
Joined: Dec 2003
Posts: 19,384
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From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
Rear Axle Limited-Slip Differential: SAE 75W-90 Synthetic Axle Lubricant, GM P/N 12378261 (Canadian P/N 10953455) or equivalent meeting GM Specification 9986115.
Tech Contributor
Joined: Dec 2003
Posts: 19,384
Likes: 87
From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
No need to change it. If I was going to change it anyway, I'd use the specified lubricant. JMHO
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From: Maker of Sharp Objects, AL - Roll Tide
St. Jude Donor '10-'11-'12-'13-'14-'15-'16-'17
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Sounds to me like your dealer needs the profit from a rearend job and they thought you seemed like a good candidate.
Racer
Joined: Apr 2005
Posts: 490
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From: Edmond OK
actually, not sure sure its the usual b.s. I've had an ongoing "noise" from my diff for 3 years. It's been to the dealer three times for this. Each time, they've changed the fluid. Works ok for couple months, then sound comes back. Basically a grinding, slow speeds, when turning. Best way to demonstrate to service guy was lazy s in the parking lot. a groan, groan, groan sound.
Took it back 2 weeks ago and hit them hard, documented the crap out of them, and asked for them to replace diff. They wouldn't do it. They cited that GM bulletin, said they have had other vettes in there over last year with same sound problem, and the "new" super fantastic, whatever lube will do the trick this time.
So, I think there is a small problem out there, at least I've had it. I hope this time is the charm,and the sounds stops coming back.
I've got 31,000 miles on mine
Took it back 2 weeks ago and hit them hard, documented the crap out of them, and asked for them to replace diff. They wouldn't do it. They cited that GM bulletin, said they have had other vettes in there over last year with same sound problem, and the "new" super fantastic, whatever lube will do the trick this time.
So, I think there is a small problem out there, at least I've had it. I hope this time is the charm,and the sounds stops coming back.
I've got 31,000 miles on mine