Differential fluid change...Additive??
Thread Starter
Drifting
Joined: Apr 2004
Posts: 1,888
Likes: 21
From: Olathe, Kansas
Differential fluid change...Additive??
I've read so many different opinions on changing the differential fluid, I'm not sure which is best. I've got the Redline 75W-90 gear oil with the additive already in the bottle. Should I add the GM additive or not?
What are you using, and what have been the results?
What are you using, and what have been the results?
Thread Starter
Drifting
Joined: Apr 2004
Posts: 1,888
Likes: 21
From: Olathe, Kansas
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
I have Redline in my coupe and Amsoil in the wife's coupe and didn't have to add additional additive to either. That said, you may need to add some to quiet down your diff after filling the diff with one of these although it's not usually required. You'll want to just add a little bit at a time and then drive the car to see if this cures it as you can add too much additive. You should not need to add the whole bottle of additive.
Melting Slicks
Joined: Jan 2007
Posts: 3,021
Likes: 133
From: Conejo Valley CA
I just had my entire differential taken out,
http://forums.corvetteforum.com/show....php?t=2077727
When it was put back, I used Mobile-1 75W 90 LS (the LS designation means the limited slip additive is already there). I did not add any additional additive.
http://forums.corvetteforum.com/show....php?t=2077727
When it was put back, I used Mobile-1 75W 90 LS (the LS designation means the limited slip additive is already there). I did not add any additional additive.
Thread Starter
Drifting
Joined: Apr 2004
Posts: 1,888
Likes: 21
From: Olathe, Kansas
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Advanced
Joined: Dec 2006
Posts: 85
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From: Queens NY
I just had my entire differential taken out,
http://forums.corvetteforum.com/show....php?t=2077727
When it was put back, I used Mobile-1 75W 90 LS (the LS designation means the limited slip additive is already there). I did not add any additional additive.
http://forums.corvetteforum.com/show....php?t=2077727
When it was put back, I used Mobile-1 75W 90 LS (the LS designation means the limited slip additive is already there). I did not add any additional additive.
Same here... I did do a few forward and reverse figure 8's in a parking lot, and haven't had any noise at all.
Tech Contributor
Joined: May 2008
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From: Somers, CT and Clermont, FL
St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16
They also say no W.O.T. for the next 500 miles, but that takes alot of self control to do!
Thread Starter
Drifting
Joined: Apr 2004
Posts: 1,888
Likes: 21
From: Olathe, Kansas
Differential fluid change update
After 140 miles, it's like a brand new car! The groaning and creaking on tight turns is completely gone. I used the Redline 75w-90 without adding additional additive. No special driving after the change, just got in and drove it! The whole process took 20 minutes. I find it hard to believe dealers charge $140 for this service, it's that easy! 
Team Owner
Joined: Mar 2001
Posts: 25,889
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From: Virginia Beach
CI 3-5-6-7-8 Veteran
I run Amsoil in mine... I dont add any GM additive, no issues. After swapping I go do a few figure 8s to get it all worked in. If you do hear any chatter its easy to pull the fill plug and squirt a little additive in.
