I just had an issue on my 2019 Chevy Colorado while on vacation in WV. While driving down the highway it began to shudder.
I took it to the nearest Chevy dealer who took it right in. The service dept. Told me that there was a service bulletin put out that certain Chevy models were outfitted with a transmission fluid that retired moisture and that this would result in the torque converter losing torque causing the transmission to shudder.
The bulletin (18-NA-355) stated that a transmission flush with a synthetic transmission fluid would correct the problem.
Intook the vehicle to the dealer (Ourismon in Bowie, MD) I purchased it from since I have had all maintenance performed there and showed them the bulletin. They told me a transmission flush is routine maintenance and not covered by warranty.
They gave me the number for GM customer service to submit a claim for rebate. After a couple of weeks I got an email back stating my truck was purchased used (It was new) and the warranty would not be covered.
After I called them back to tell them I purchased it new, they said that they are working to resolve this issue and that they would contact the dealer to cut me a rebate. I got an email back today stating that this was considered routine maintenance and would not be covered. My question to them was “Why would I get a transmission flush at 39000 miles for more than $500.00?”