Changing diff fluid
Thread Starter
Le Mans Master
Joined: Oct 2012
Posts: 6,391
Likes: 1,453
From: South Dakota
Changing diff fluid
I'm thinking of changing my differential fluid before my trip to Eureka Springs in early Oct for Corvette weekend. There are no problems or noises or such, just thinking of changing it (or is it really even necessary?). I will do it myself. what is the best type/brand/viscosity etc to replace it with?
Racer
Joined: Jul 2013
Posts: 265
Likes: 27
From: Moncton NB
I didn't do it myself, but I just had mine changed based on the advice from this forum. I have a 2010 GS with 14000 miles and the fluid was very dark and cloudy. I was not having any issues, but based on the discussion it's good preventative maintenance if you haven't done it yet.
I used the GM fluid. If you search the forum you will finds lots of info about changing diff fluid.
I used the GM fluid. If you search the forum you will finds lots of info about changing diff fluid.
Race Director
Joined: Sep 2000
Posts: 11,143
Likes: 1,913
From: Missouri City, TX
I'm thinking of changing my differential fluid before my trip to Eureka Springs in early Oct for Corvette weekend. There are no problems or noises or such, just thinking of changing it (or is it really even necessary?). I will do it myself. what is the best type/brand/viscosity etc to replace it with?
Melting Slicks
Joined: Jan 2013
Posts: 2,576
Likes: 237
From: Murphy NC
I have been doing mine every 10K, that is when the chattering comes back.
I say change it. It good to do regular maintenance on your vehicle whether it is broken or not.
That is forty dollars well spent.
Use the GM Oil. I found that to be the best.
I say change it. It good to do regular maintenance on your vehicle whether it is broken or not.
That is forty dollars well spent.
Use the GM Oil. I found that to be the best.
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Drifting
Joined: Aug 2012
Posts: 1,587
Likes: 5
From: central NJ
I assume it's an 08 by your name? If so i would say change it no matter the miles. I changed mine recently ('06 with 27k miles) and it was BAD. Black as can be, and it didn't have the consistency of what it should, more runny or liquidy as opposed to oily. I had no symptoms of anything but changed anyway. I used 2qts amsoil severe gear and their 4 oz additive and it feels great!! I highly recommend the amsoil with the additive.
PS it only takes about 1.7 qts total, and make sure your car is 100% level....
PS it only takes about 1.7 qts total, and make sure your car is 100% level....
Racer
Joined: Feb 2005
Posts: 313
Likes: 3
From: Southeast - Alabama, Georgia, & Tennessee
I'm thinking of changing my differential fluid before my trip to Eureka Springs in early Oct for Corvette weekend. There are no problems or noises or such, just thinking of changing it (or is it really even necessary?). I will do it myself. what is the best type/brand/viscosity etc to replace it with?
SAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 89021677, in Canada 89021678) meeting GM Specification 9986115. With a complete drain and refill, add 4.7 ounces (140 ml), or 6.8 ounces
(200 ml) for ZO6 Models, of Limited-Slip Axle Lubricant Additive
(GM Part No. U.S. 1052358, in Canada 992694) where required.
See Rear Axle on page 5-51.
Used Mobil 1 when I had a 2008 Coupe and it took the chatter away and overall was much more quiet
Race Director
Joined: Apr 2007
Posts: 16,025
Likes: 1,656
From: Toronto, Canada
C7 of the Year - Unmodified Finalist 2021
would clicking sounds be considered chattering when driving at slow speeds or changing gears from D to R or vice versa?
Melting Slicks
Joined: Dec 2006
Posts: 2,694
Likes: 106
Mine was like that too, with only 3K miles. A lot of crap in there from assembly. MUCH better to change it early IMO. After that, you can leave it for much longer. I was also having 'chatter' on my new '12 GS, so guess GM didn't use the good stuff from the factory. And yes, the Dexron LS cured everything. Remember on the GS you need to run the engine on the air in 2nd gear for a minute, to fill up the cooling lines. Then top off as needed (car must be level, remember). I did the tranny at the same time, to dump the non-synthetic stuff, and used Amsoil TorqueDrive instead. Good luck.
Melting Slicks
Joined: Jan 2013
Posts: 2,576
Likes: 237
From: Murphy NC
First gear, right or left turn the clutches will make a kind of grinding clunky noise.
Advanced
Joined: Feb 2013
Posts: 78
Likes: 0
From: West Palm Beach Florida
Instructor
Joined: Aug 2005
Posts: 171
Likes: 2
From: Washington Utah
I didn't do it myself, but I just had mine changed based on the advice from this forum. I have a 2010 GS with 14000 miles and the fluid was very dark and cloudy. I was not having any issues, but based on the discussion it's good preventative maintenance if you haven't done it yet.
I used the GM fluid. If you search the forum you will finds lots of info about changing diff fluid.
I used the GM fluid. If you search the forum you will finds lots of info about changing diff fluid.
Melting Slicks
Joined: Jun 2007
Posts: 2,673
Likes: 9
From: Upstate New York
OM has the following...
SAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 89021677, in Canada 89021678) meeting GM Specification 9986115. With a complete drain and refill, add 4.7 ounces (140 ml), or 6.8 ounces
(200 ml) for ZO6 Models, of Limited-Slip Axle Lubricant Additive
(GM Part No. U.S. 1052358, in Canada 992694) where required.
See Rear Axle on page 5-51.
Used Mobil 1 when I had a 2008 Coupe and it took the chatter away and overall was much more quiet
SAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 89021677, in Canada 89021678) meeting GM Specification 9986115. With a complete drain and refill, add 4.7 ounces (140 ml), or 6.8 ounces
(200 ml) for ZO6 Models, of Limited-Slip Axle Lubricant Additive
(GM Part No. U.S. 1052358, in Canada 992694) where required.
See Rear Axle on page 5-51.
Used Mobil 1 when I had a 2008 Coupe and it took the chatter away and overall was much more quiet
There is no need to add friction modifier with the new stuff.
OP - It's a pretty easy process. The fact that GM went though several iterations of recommending different fluids before finally settling on this one tells me there was an issue there - why not run with the latest?
This member did a write up: LINK
Last edited by LMB-C6; Aug 21, 2013 at 08:09 PM.
Melting Slicks
Joined: Jan 2013
Posts: 2,576
Likes: 237
From: Murphy NC
Mine was making the chatter noise at low speed turns especially in reverse (automatic). Took it in to get the tranny fluid changed and was told the dealer had to do it cause I'm over 100K. They were afraid the fluid was becoming sludge and putting in new fluid would change the way the tranny shifted, if at all. Put they did suggest differential change...so I did that along with oil change. $140 out the door for both. Imagine my surprise when the chatter noise had stopped! And it evens seems to shift better when in the gas! So i researched and found on the forum that indeed there is a TSB for this......
What a difference.
I have done the Differential twice since and it just keeps getting better.
I am 13K from 100K. I can not wait to swap the AT fluid again.
I also went to 10w-40. The engine feels so much more solid at start up and while driving.