10l80 overheating

Nino379x · March 22

Hello everyone, I a proud owner of a 2020 Z71 Trail Boss LT. Lately I’ve noticed trans temp going over 220. My 5.3 is paired with a 10L80 transmission and seems to have an internal thermal bypass valve. Been looking for a solution can’t find one. Anybody no a good fix for this. I’d really appreciate the info thanks.

Coastie05 · March 22

How old is the fluid and how many miles do you have on the fluid?

Nino379x · March 22

So I bought the truck about 11/2 yrs ago, trans has not given me any trouble. Truck has 154miles in it was going to change the transmission fluid, but haven’t cuz I wanted to get all parts needed before starting . I bought Mobil 1 ULV blue label oil. Worked great on my Escalade when it starts to shutter

Coastie05 · March 22

1 hour ago, Nino379x said:

So I bought the truck about 11/2 yrs ago, trans has not given me any trouble. Truck has 154miles in it was going to change the transmission fluid, but haven’t cuz I wanted to get all parts needed before starting . I bought Mobil 1 ULV blue label oil. Worked great on my Escalade when it starts to shutter

I may go against the grain here but I would change the fluid since it does degrade over time. I know a lot of ppl would say not to change it or flush it since you’ve never changed it but I really think this may fix your problem.