MN6 and Rear Diff fluid
Thread Starter
Team Owner
Joined: Mar 2006
Posts: 53,282
Likes: 3
From: God Bless America
MN6 and Rear Diff fluid
I am planning on changing the fluid in both the manual transmission and my rear diff. I was wonder what other forum members have used and which types of fluid they would suggest for both applications. For the rear I was thinking about Redline 75w/140 synthetic based on information I read on the DTE link, but I have seen other brands and types listed as well. For sure I don't want to make a mistake with this change where I do more harm than good, so thought I would ask those with more experience for some input. Your thoughts and comments would be appreciated. 
Le Mans Master
Joined: Jan 2005
Posts: 5,611
Likes: 5
From: Thousand Oaks California
Differential: SAE 75w-90 API GL-5, Synthetic
For the Manual Transmission GM part No. U.S. 888618, which is what use to be Dexron III, Specification "H", but GM's license agreement has expired on the use of the name "Dexron III".
For the Manual Transmission GM part No. U.S. 888618, which is what use to be Dexron III, Specification "H", but GM's license agreement has expired on the use of the name "Dexron III".
Safety Car
Joined: Jan 2006
Posts: 4,598
Likes: 78
From: Miami FL
2020 C6 of the Year Finalist - Unmodified
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16,'17,'18-'19-'20-'21-'22
Royal Purple Synchromax, installed with 1200 miles on the C6, smoothed out the shifting for me.
Team Owner
Joined: Jan 2004
Posts: 38,772
Likes: 621
From: Boston MA
St. Jude Donor '06-'07-'08,'12-'13
How hard is it to change ?
Where do you fill it back up from ?
How do you check how much is in there ?
Thanks
Where do you fill it back up from ?
How do you check how much is in there ?
Thanks
Last edited by burtonbl103; Aug 29, 2006 at 06:31 AM.
Team Owner
Joined: Dec 2002
Posts: 32,074
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From: San Francisco CA
It's Dexron 6 now which is semi-synthetic. The rear end diff is synthetic factory fill. Manual says no need to change unless you have a problem or it is leaking as I was going to do the same but after hearing about the TSB and talking with some Vette techs on the rear end I just thought "If it ain't broke don't fix it".
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Racer
Joined: Jan 2005
Posts: 310
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From: Orange County CA
Originally Posted by LS WON
It's Dexron 6 now which is semi-synthetic. The rear end diff is synthetic factory fill. Manual says no need to change unless you have a problem or it is leaking as I was going to do the same but after hearing about the TSB and talking with some Vette techs on the rear end I just thought "If it ain't broke don't fix it".
