A8 flush
Thread Starter
Instructor
Joined: Aug 2015
Posts: 165
Likes: 48
A8 flush
I know there’s lots in the forum regarding this and I’ve more or less looked at what’s been said. Opinions are just that but some are more expert than others.My 18 A8 definitely has the old hydrophilic ATF. While I’ve not had any major shudder or hard engagement the car does seem to a perceptible loss of smoothness in engagement now that it sits more since its not my daily driver. Seems intuitive the the new Mobil ATF is desirable even if no major problems. I’ve read the flush service instructions. Not done correctly your definitely asking for problems. So do we fix something that’s not broken. Looks like GM does not require Dealer confirm major problem,just owner complaint to do flush.Obviously not a big deal but as for most of us it is a little bit of pain to schedule service, take car in, come back etc.
Popular Reply
Sep 17, 2020, 12:14 PM
Le Mans Master
Joined: Nov 2015
Posts: 7,382
Likes: 3,501
From: Lake Havasu City Arizona
You can't predict the future. The A8 is fine until it isn't. For peace of mind I would have the new fluid installed. Most never develop the issue.
Le Mans Master
Joined: Nov 2015
Posts: 7,382
Likes: 3,501
From: Lake Havasu City Arizona
You can't predict the future. The A8 is fine until it isn't. For peace of mind I would have the new fluid installed. Most never develop the issue.
Last edited by joemessman; Sep 17, 2020 at 12:14 PM.
Melting Slicks
Joined: Dec 2011
Posts: 2,509
Likes: 946
From: Western New York
I agree with joemessman that you can't predict the future and the peace of mind thing. That is why I had the Triple Flush done on my 17 GS which had NO symptoms of shudder. First why not have the correct fluid in tranny. My thought was why not do fluid change and possibly prevent more complicated and expensive repair which might show up after all warranties have expired. Regarding dealer I called and talked to service manager about 18-NA-355 and procedure and felt comfortable with them doing work. I also use the Range Device on my GS and Sierra pick up.
Advanced
Joined: Mar 2017
Posts: 50
Likes: 18
Make sure the service writer knows the procedure , has the tools provided by GM , The flush uses 5 gallons of LV ATF HP blue label . The Tec has preformed this before and knows the torque setting on the under shields 24 bolts . 22 13mm bolts at 20 fps and 2 18mm bolts at 74 fp . Stress the clean up . The drips on my garage floor spoiled the whole thing for me . Get it done .
Pro
Joined: Dec 2017
Posts: 687
Likes: 102
From: Albany NY
My '17 GS has had 2 with the "New" fluid. I still have a vibration/warbel sound between 1,100-1,300 RPM with slight acceleration in any gear all the time. It's been in the shop for it's 3 trip this year for the past 5 days.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
5 Best & 5 Worst Corvette Daily Drivers
Joe Kucinski
The Headlights of Every Corvette Generation Explained
Joe Kucinski
5 Best & 5 Most Overrated Corvette Track Packages of All Time!
Joe Kucinski
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
Safety Car
Joined: Mar 2018
Posts: 4,754
Likes: 1,651
You're on the wrong thread. Your issue relates to the carrier /differential. I had to have my carrier replaced on my 19GS to fix the problem you are experiencing. Use the search here. Search for warble and differential. Many threads posted that talk about this.
Le Mans Master
Joined: Nov 2015
Posts: 7,382
Likes: 3,501
From: Lake Havasu City Arizona
Le Mans Master
Joined: Nov 2015
Posts: 7,382
Likes: 3,501
From: Lake Havasu City Arizona
Instructor
Joined: Mar 2018
Posts: 222
Likes: 138
From: Fountain Hills, AZ
It's worth doing. My supercharged 650 rwhp '16 had the shudder really bad. I did the triple flush and have had no more shudders since. I did the flush 1 1/2 years ago and no issues (fingers crossed).
Last edited by ricmalaz; Sep 19, 2020 at 04:00 PM.