I bought a 2017 GS automatic vert in June. Within the first 500 miles, I felt a vibration/humming sound which seemed to be under the passenger side floor board. This occurred at a low rpm rolling speed at approximately 30 mph or less. I recall hearing this 2 or 3 time since I’ve had the car. It may have happened more because I have only put about half of the 3000 miles that are on the car. Was I experiencing the dreaded warble?

I was was not aware of the TC issues at that time, but the more I read about these issues, the more concerned I become. I actually documented the problem in an online Chevy survey. Chevy actually called me about the comments in my survey but did not appear concerned about the noise that I experienced. Had I been aware of the TC issues at that time, I would have been more aggressive with my questions.

I live in Ohio and put the car away for the winter. It is a pleasure vehicle only and I don’t anticipate putting more then 10,000 miles a year on it. I can see this going bad for me if the TC issue doesn’t manifest itself before my warranty times out.

It seems to me that GM is not being proactive in addressing the issue. I understand there are new part numbers for replacement TCs, but what exactly has been changed to correct the problem?

 

It bothers me aswell, After 1 day in service I get a call from the dealer telling me my car is ready for pick up.

I have to ask how the triple flush is done, Drain, Fill, and Drive?
All in 1 day?? 3 times?

GM is getting ready to start production on the 2019s. But I have read a post or two about the same issue on the 2018s. So I ask what is the replacement part???

My wife said I hope they get your car fixed before 60k miles

More important is I hope every one has a MERRY CHRISTMAS with family

 

Sorry to say but you can be 90% sure that your TC is the issue. I had same issue with mine at 9500 miles, took into dealer once and was told they could not replicate my issue, went back 2 weeks later with information and a copy of the latest TSB, they changed the TC and It is GREAT AGAIN. I am in Leesburg as well and if you are interested in where I took it for service or other information just holler at me

Good Luck

 

I just picked up my car 30 minutes ago. Going over the paperwork it says they found a shudder @ 48 mph and again @ 65 mph and a slip speed @ 22HZ.
Then they found a bulliten # 16-NA-175 Replaced transmission filter, changed fluid to HP DEXON, flushed cooler lines and coolers flush code 0BF8EE7

FILTER # 24274402
FLUID # 19353429


Thats what is on the paper work

 

brought mine in 2 weeks ago for same symptoms, they said the flush bulletin was outdated and they changed my converter. it fixed the problem.

 

GM's been around and around about the correct fix since 2015. It started with a full tranny replacement, then the 3x-flush followed by a TC change and 3x-flush, back to the 3x-flush only around the beginning of this year, and now apparently are back to doing both. I presume the 3x-flush didn't work on enough cars, like Jadge Juechter mentioned when they first tried that method two years ago.

BTW, the latest part number I have for fluid is what Jim Spitzer reported (19353429), which is Mobil 1 HD LV (low-viscosity) ATF. I don't know what they used before that, but there was a change at some point in the A8's sordid history. FWIW, the latest part number I have for the TC is 24280631, which has been around now for almost one year and is the third revision. It would be good to know how many of these have come back for repeat replacements, but wouldn't bet they have a permanent fix for the TC issues even now. Time will tell.

 

Today I was able to get the car out after yesterdays service. I don't think it's 100% at first but as the day went on it did feel better. I could tell it shifted smoother. So I think I will keep putting miles on to what happens. I bet if GM put the mobil 1 in the car when built we would not have this problem.
I feel after 11k miles on my car the damage is already done to the TC.
I could be wrong. (the jury is out)At least the service writer said that if it happens again they will replace the TC.

 

Little update, This past Fri. My wife an I went on our dinner date. On the way home I was driving about 46/48 mph in econ. mode and my wife ask if we had a flat tire.
I put about 500 miles on the car since the trans flush. Now I guess I have no choice but to return to the dealer for a TC change out. Or what ever they say.

 

I am willing to bet you don't get a torque converter.

They will put the car back on the computer and drive it with a sensor connected.
The graph won't show a problem with the transmission but point to something else.

Have your tires been road force balanced?

 

If that happens again, you can quickly go to Manual mode which eliminates V4, and see if anything changes. If the problem disappears, go back to Auto and let it go into V4 to see if the problem returns.

The more information you can give the people working on the car, the more likely they are to get it fixed sooner.

 

It appears the transmission flush works on some cars and others it doesn't work. Who knows why this problem continues.

 

It's good you went into failure soon after the fluid change. Get the TC behind you and you will be good to go! Sorry for your issue, but better now than later. Have a good one!