C7 auto trans
Drifting
Joined: Jun 2015
Posts: 1,843
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From: Lagrange KY
Yes, you should be concerned about this. If it’s the automatic A8, and there is no record of it having been previously accomplished, you’re risking potential driveline problems. Check the GM VIS report to see if it has already been done. Any GM dealer can provide that computerized report. The original fluid had issues related to moisture retention that has been attributed to some transmission related problems. There are many many threads discussing the problems. Shuddering, hard shifts, etc.. The fix is a triple flush of the old fluid and replacement with a new and improved formula. Be sure to get that new formula and the work is performed by a competent GM dealership familiar with the process. Be forewarned that it is a rather expensive procedure. Probably close to $1000.
I Love My C7
Joined: May 2023
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From: Go Bucks!…
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Google “C7 corvette shudder” and you’ll get hits from this forum…and start reading.
Here is a start for you…if you’re mechanically inclined it’s possible to do flush yourself. Not cheap either way.
Good luck! Keep us in the loop
https://www.corvetteforum.com/forums...-tracking.html
Here is a start for you…if you’re mechanically inclined it’s possible to do flush yourself. Not cheap either way.
Good luck! Keep us in the loop
https://www.corvetteforum.com/forums...-tracking.html
Team Owner
Joined: Jul 2004
Posts: 28,357
Likes: 3,253
From: Hartford WI
Yes, you should be concerned about this. If it’s the automatic A8, and there is no record of it having been previously accomplished, you’re risking potential driveline problems. Check the GM VIS report to see if it has already been done. Any GM dealer can provide that computerized report. The original fluid had issues related to moisture retention that has been attributed to some transmission related problems. There are many many threads discussing the problems. Shuddering, hard shifts, etc.. The fix is a triple flush of the old fluid and replacement with a new and improved formula. Be sure to get that new formula and the work is performed by a competent GM dealership familiar with the process. Be forewarned that it is a rather expensive procedure. Probably close to $1000.
CF Community Team
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From: Pittsburgh
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There is a boat load of information on this forum concerning the A8 trans shudder, use the search feature to read about them
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Melting Slicks
Joined: Dec 2004
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Yes, you should be concerned about this. If it’s the automatic A8, and there is no record of it having been previously accomplished, you’re risking potential driveline problems. Check the GM VIS report to see if it has already been done. Any GM dealer can provide that computerized report. The original fluid had issues related to moisture retention that has been attributed to some transmission related problems. There are many many threads discussing the problems. Shuddering, hard shifts, etc.. The fix is a triple flush of the old fluid and replacement with a new and improved formula. Be sure to get that new formula and the work is performed by a competent GM dealership familiar with the process. Be forewarned that it is a rather expensive procedure. Probably close to $1000.
Team Owner
Joined: Jul 2004
Posts: 28,357
Likes: 3,253
From: Hartford WI
My Rick Hendrick Chevy dealership charged $599. This was 1.5 yrs ago. The Stingray had 24,000 miles and they said the car did not need a triple flush but i had it done anyway because I do not play around with transmissions. I have been stranded twice on the interstate highway due to transmissions.
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Team Owner
Joined: Jul 2004
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From: Hartford WI
That is what usually happens when you ask for a price and not ask how they got the number. I've told the appointment clerk to show me the itemized breakdown and not toss me a number.
I Love My C7
Joined: May 2023
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From: Go Bucks!…
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I am thinking it was fixed by the Mid 2019 models...my late 2017 just missed it. If I stumble across the end date I will post it.
Last edited by Blackcherry20; Aug 14, 2025 at 11:04 AM.
Team Owner
Joined: Jul 2004
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From: Hartford WI
Safety Car
Joined: Nov 1999
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From: Green and Wet Western Oregon
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Print a copy of TSB 18-NA-355 and take it with you when you go to the service writer. Make damn sure they know that they DO NOT need to test drive the car to verify the problem. Just do the procedure as detailed in the TSB.
This procedure pertains to all A8 transmissions built before February 2019.
This procedure pertains to all A8 transmissions built before February 2019.
Team Owner
Joined: Jul 2004
Posts: 28,357
Likes: 3,253
From: Hartford WI
Print a copy of TSB 18-NA-355 and take it with you when you go to the service writer. Make damn sure they know that they DO NOT need to test drive the car to verify the problem. Just do the procedure as detailed in the TSB.
This procedure pertains to all A8 transmissions built before February 2019.
This procedure pertains to all A8 transmissions built before February 2019.
On the day of, make sure they know it's him or nobody. Check invoice to know if 24 quarts of fluid and 1 filter and at least 2.8 hours was billed. Don't forget to tip your mechanic if you don't see issues.
Last edited by aklim; Aug 14, 2025 at 01:18 PM.
Safety Car
Joined: Nov 1999
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From: Green and Wet Western Oregon
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I would make sure you talk to the Corvette Certified tech and tell him what you want done. The service idiot is there to book the appointment. He writes all kinds of crap and the tech executes. You may end up getting 1 pan drop and 8 quarts of fluid, think you got a great deal like the guy several posts above. Specify that THIS tech and nobody else works on the car. Tell them you can reschedule if needed.
On the day of, make sure they know it's him or nobody. Check invoice to know if 24 quarts of fluid and 1 filter and at least 2.8 hours was billed. Don't forget to tip your mechanic if you don't see issues.
On the day of, make sure they know it's him or nobody. Check invoice to know if 24 quarts of fluid and 1 filter and at least 2.8 hours was billed. Don't forget to tip your mechanic if you don't see issues.
Team Owner
Joined: Jul 2004
Posts: 28,357
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From: Hartford WI
IDK. I pass a couple of nearby ones because they aren't able and/or willing to meet my needs. How far is the nearest one with a technician that is certified?
Pro
Joined: Nov 2014
Posts: 506
Likes: 75
When I bought my 2016 c7 corvette in 2021 I saw the paperwork it had to have a seal replaced on transmission. With them doing that at a gm dealer should I still get it flushed out 3 times. How do you know transmission needs to be done. What's the signs I should be looking for or feeling. Thanks