My stock 4l80 will run at 110-130 under normal driving, 150-160 when I beat on it. This tranny has about 10K miles on it using the factory cooler.

My original tranny ran similar temps until the dealer replaced my cooler lines, then it ran so hot:



It lasted about three days.

 

What is everyone using to get their temps? I've noticed that the trans temp in the cluster is WAY off. I have my Aeroforce gauge set to monitor trans and coolant temps.
And I bypassed the radiator.

 

I just read off the OEM cluster but it was spot on with what HP Tuners was showing also.

 

Yea, it does get pretty warm when you do several back to back WOT runs.

Maybe they made it alittle more accurate than the older models.

 

i got 03 escalade gauges an my tranny temps right on

 

Same here, running a 3200 stall

 

AndysC3, maybe your cluster stepper motor is bad? I've seen a few that are off a bit, but the majority of clusters with trans temp gauges are pretty close.

It should also be said that it seems to be common that 80e's run hotter than 60/65e's by about 30-40 degrees, from what I've noticed. Even with 40K coolers.

 

I just use efi live or a scan gauge 2.
And since my scan gauge is in my buddys truck i just used the laptop

 

Do you have the cold weather bypass. I kinda need one for the winter, but it makes me a bit leery that it doesn't fully opens until 180*

 

dewey