My 17 ZO6 with A8 has 34k miles.
it has begun the exhibit a pause and a noticeable bump from 3-4. I’ve owned it for a couple years and drive it conservatively. However, I have reason to believe that the previous owner tracked it and drove it pretty hard.

My son had a similar issue with his Ford Explorer. My favorite mechanic recommended Amsoil ATF. It solved his problem and extended the life of the Explorer trans to over 200k miles before he sold it. It may still be going.

So what is the Forum CW about Amsoil ATF in the C7 A8?

Thanks for your replies

 

I would take to the Chevy dealer and have the triple flush done. It was no charge when I had mine done a couple of years ago.

 

Stick with Mobil 1 'Blue Label'.

Way too many issues over the years to start experimenting with 'other' ATF fluids on the A8.

 

I just had a "Triple Flush" done at a Chevy dealership (March 2024)
The fluid they used was "Mobil 1 Synthetic LV ATF HP". 24 Quarts. Fixed problem.

I just purchased a 2017 Grand Sport with 10,500 on it. I am owner 3 and as far as I can tell it still had original ATF fluid from build date of 2016.
I had never driven a Corvette. The thing that I noticed first was "exhibit a pause and a noticeable bump from 3-4".
Service Bulletin No.: 18-NA-355 from April, 2020 States " Some customers may comment that their vehicle is experiencing a shake and/or shudder
during light throttle acceleration between 25 and 80 mph steady state driving when transmission is not actively shifting gears. The condition may be
described as if they are driving over rumble strips or a concrete road surface with rough expansion joints." I also had these symptoms.
Condition: This condition may be due to Torque Converter Clutch (TCC) Shudder." Took me a while to figure out that you can
display on your dash when your car is going from 8 cylinder to 4. That may have something to do with it also.
I have a 90 day/ 4 thousand mile warranty from the dealership where I purchased the car and they paid the $1200 cost of the ATF Flush. I am happy with the results!

 

Mobil 1 Synthetic LV ATF HP,,,, might be good,,,,,, but I wouldn't use it just because a dealer used it. Do some more research.

Edit: I understand they still recommend the ACDelco 10-9394 in the 2014 A6.

 

As some have already said - Use Mobil 1 Syn LV ATF HP 124715 - This is what was released in 2019 as the latest & greatest ATF for the A8. Our 2016 Z51 got the triple flush with this fluid in Sept 2019. At that time it was done under warranty - Not sure what the current status is.

Best wishes on your endeavor.

 

Bump in 3rd to 4th gear shift, ask dealer or any competent shop to do a garage relearn
(you can thank me later )

Dave

 

Is a garage relearn a return to factory settings of ?

 

TCM (Transmission Control Module).

Triple flush as the others stated with the correct newest magic elixir. If they insist on charging you an arm and two legs, you can do it yourself. It is not terribly hard or that messy as you do not need to drop the tranny pan which is a royal PITA. There are many threads here that show you how to do it yourself.

 

The A8 is a adaptive learning transmission , drive it like you drive your fathers Buick can lead to sloppy shifts , banging into gear complaints or shift flair . Every once in a while you need to drive it hard .....
A Garage Relearn process is a bit more than a factory reset , the TCM when put in relearn mode, will "learn" the pressures and the release times for each clutch pack and then it will clear any adapts that were learned during the previous drive cycles. Then for the next 100 miles it will be in a learning mode , monitoring the input shaft and output shafts speed during shifting looking for the correct preasure and release speeds to make a perfect shift every time . During this period, it is important that you vary your driving style from normal everyday driving to diving the car like you stole it .... !!!

You might experience a few sloppy shifts during this time but once the process is complete the trans will shift perfectly

Its a little scary the first time you do it ( I do my own repairs ) as the trans makes all kind of crazy sounds as it completes the process

A garage relearn should always be the first thing that is performed for any complants of sloppy shifting , banging into gear etc . To often its not and it leads to an unhappy customer if the dealer starts shooting the parts cannon at the car or as everybody here is saying, " Just replace the fluid" .. fluid has nothing to do with a sloppy shift , most people say they got the fluid flush and their trans shifts great don't even realize that a good dealer would also perform the relearn and that's what's making it shift great

Dave

 

This

 

ATF fluid:

A6 doesn't care.

A8 does, use only the Blue Label Mobil 1 ATF.

Do this and be happy once again.

 

there was a technical service bulletin (TSB) issued to use the Mobil 1 LV atf Hp fluid to solve the shift problems for all the 8 speeds.

 

Out of warranty cost at dealers is $1000.00 asof today 5/10/2024