M7 owners
Thread Starter
Pro
Joined: Apr 2014
Posts: 568
Likes: 109
From: South Carolina
M7 owners
M7 owners when do you change your M7 fluid (im at 12K) and is there a better fluid than 88861800GM and would it be warranty compliant
Amsoil,redline D4. royal purple syncromax Ect. Ect. thanks
Amsoil,redline D4. royal purple syncromax Ect. Ect. thanks
Le Mans Master
Joined: Sep 2003
Posts: 8,847
Likes: 795
From: Longview Texas
I would stick with the GM fluid.
Not sure how other fluids affect the internals of C7 transmission, but on C5 going to synthetic or fluid other than GM caused some shifting problems. A friend tried that and when he went back to GM fluid, the problems went away.
Not sure how other fluids affect the internals of C7 transmission, but on C5 going to synthetic or fluid other than GM caused some shifting problems. A friend tried that and when he went back to GM fluid, the problems went away.
Burning Brakes
Joined: Feb 2011
Posts: 833
Likes: 470
From: Goodyear AZ
I changed my transmission fluid out at about 3k miles and used Amsoil. I remember tho, the stock fluid was not synthetic and I did a lot of research at the time to make sure the Synthetic Amsoil fluid was ok. The service advisor I have known for a long time and who is also a Vette nut confirmed it would not be an issue and thought it was fine to switch out. I have had it in two years now w/ no issues, it shifts smoother than with the factory fluid as has been the case w/ any vehicle I switch the trans fluid to Amsoil on. I did not switch out the diff fluid as it seemed harder to get to w/ the e-diff on the Z-51. Just my 2 cents.
Le Mans Master
Joined: Mar 2016
Posts: 9,165
Likes: 4,011
From: 2019 CMG Z06/ZR1
My vette only has 900 miles, so can't help there. However, on my 1LE Camaro, which I track occasionally, I have done rear end and trans fluid changes. With all of my research, and I know some will strongly disagree, but I found no reason to go outside of OEM fluids. They even come premixed with additives so nothing to second guess. Hope this helps.
Le Mans Master
Joined: Oct 2011
Posts: 7,079
Likes: 1,922
From: DFW, Tejas!
My vette only has 900 miles, so can't help there. However, on my 1LE Camaro, which I track occasionally, I have done rear end and trans fluid changes. With all of my research, and I know some will strongly disagree, but I found no reason to go outside of OEM fluids. They even come premixed with additives so nothing to second guess. Hope this helps.
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Advanced
Joined: Jul 2015
Posts: 83
Likes: 69
From: Richland, Washington
Changed both the differential and transmission at 1,000 and 5,000 miles. Royal Purple Synchromax for the trans and Mobil1 75-90 on the first diff change and Lucas 75-90 for the second. 2016 with 14,500 miles currently, definitely glad I did the first change as they both had a metallic look to them. Second was much cleaner so will probably wait until 20,000 for the third change. A little smoother shifting
with the Synchromax in the trans.
with the Synchromax in the trans.
Racer
Joined: Nov 2015
Posts: 405
Likes: 176
FWIW, under normal usage the owner's manual calls for transmission fluid changes basically never, and rear axle changes at 45K mile intervals.
Under severe usage the protocol is to change the transmission fluid and rear axle fluids at 45k mile intervals.
Clutch fluid is to be changed every three years in either case.
Under severe usage the protocol is to change the transmission fluid and rear axle fluids at 45k mile intervals.
Clutch fluid is to be changed every three years in either case.
Racer
Joined: Aug 2016
Posts: 397
Likes: 39
Just the "engine" oil is free...some people swear by changing every ounce of fluid (probably the washer fluid as well) and others follow the manual, and most people sell their cars after a couple or few years.
Last edited by Bob Z.; Nov 10, 2016 at 08:43 AM. Reason: meant to state "engine"
Le Mans Master
Joined: Mar 2016
Posts: 9,165
Likes: 4,011
From: 2019 CMG Z06/ZR1
Le Mans Master
Joined: Mar 2016
Posts: 9,165
Likes: 4,011
From: 2019 CMG Z06/ZR1
Changed both the differential and transmission at 1,000 and 5,000 miles. Royal Purple Synchromax for the trans and Mobil1 75-90 on the first diff change and Lucas 75-90 for the second. 2016 with 14,500 miles currently, definitely glad I did the first change as they both had a metallic look to them. Second was much cleaner so will probably wait until 20,000 for the third change. A little smoother shifting
with the Synchromax in the trans.
with the Synchromax in the trans.
Tech Contributor
Joined: Oct 1999
Posts: 41,058
Likes: 9,821
From: Charlotte, NC (formerly Endicott, NY)
FWIW, under normal usage the owner's manual calls for transmission fluid changes basically never, and rear axle changes at 45K mile intervals.
Under severe usage the protocol is to change the transmission fluid and rear axle fluids at 45k mile intervals.
Clutch fluid is to be changed every three years in either case.
Under severe usage the protocol is to change the transmission fluid and rear axle fluids at 45k mile intervals.
Clutch fluid is to be changed every three years in either case.
Bill
Tech Contributor
Joined: Oct 1999
Posts: 41,058
Likes: 9,821
From: Charlotte, NC (formerly Endicott, NY)
FWIW, under normal usage the owner's manual calls for transmission fluid changes basically never, and rear axle changes at 45K mile intervals.
Under severe usage the protocol is to change the transmission fluid and rear axle fluids at 45k mile intervals.
Clutch fluid is to be changed every three years in either case.
Under severe usage the protocol is to change the transmission fluid and rear axle fluids at 45k mile intervals.
Clutch fluid is to be changed every three years in either case.
Bill
Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
Underline true. Plus, I think you mean "engine oil" being free, not rear, trans, etc.
Racer
Joined: Aug 2016
Posts: 397
Likes: 39