Evansdad

Update: Dealer still has it, waiting on a transmission cooler bypass valve. They had to order the part. Keeping the miles low if nothing else. How willing would Gm be swayed to offer an extended warranty or extended onstar subscription since I have had the truck for 3 weeks and only could drive it 3 times? Each time to a dealership for tranny issues.

So dealer took it for two trips and transmission temp were as follows: 20 min - 216 degrees 45 min up steep mountain - 233 degrees my trip 1/2 way home was 1.5 hours - went to 277 degrees. He said everything mechanical was fine and no codes were detected. Plan on going to get it Saturday morning. What trans temp does everyone’s 6.6 gas seem to operate at? My 2011 6.0 never goes over 200. Thanks in advance.

Help, took delivery of a 2020 2500hd double cab today and driving home the transmission overheated. It is the gas engine. Temp went to at least 277 on the gauge and it told me to pull over and idle. I had it towed to nearest dealer through road side assistance. It had a total of 150 miles on it. Can the Trans fluid be too low or too full? what else could have caused this? How much damage do you think would have already been done? thanks and waiting patiently for Monday morning to call the service dept where it was towed.