My transmission starts to overheat after about 30-40 minutes of driving. It's a new problem and began about a week or two after I had the TC installed. Otherwise it drives characteristically fine. The fluid level is fine. It has a TCI 3k stall and my sig is current. Please help.

 

Did you install an aftermarket cooler? Recommended.
How hot is your fluid getting? How are you measuring it?
Is your TC locking?

 

Curious to know the operating temp you see.

 

I only have the factory GM cooler and for the first 2-ish months after the TC install, it didn't overheat. It goes over 200, keeps climbing and I get the "transmission hot" message in my display center. Measuring it with the cluster gauge. How do you know if the TC is locking? I'm not a transmission guy! Would it run if the TC was going bad?

 

sounds too me that the lockup clutch isn't engaging anymore.
have you noticed if your turning more rpms at say any given mph than usual?
yes it will still run if the tc was going bad.

 

Yeah, that was the only small difference I noticed. Seems to hang up between shifts occasionally and stays in upper RPM's a little longer before shifting. Don't think replacing the cooler would help??

 

https://www.performancetrucks.net/fo...d.php?t=406094

This was my original thread. It's a little more descriptive.

 

A good way to test lockup is while cruising on highway. Tap brake without reducing speed and the rpm's should jump up a bit then drop back down in a couple seconds when it locks again. If it is not locking, I could see it overheating. Could also see it with a 3000 stall on a stock cooler.