4l80e Towing Issues

[dragr1]

I'm not real pleased with the towing ability of the transmission in my '00 Suburban 2500 6.0 4x4. Sometimes it seems to "ride" the torque converter for extended periods while towing. It doesn't do this all the time and it doesn't do it when climbing big hills. It seems to mostly do it on very gradual grades or on rolling terrain. For instance, when it does this, it will run 3000rpm at 60 or the same rpm at 70mph. It should run 3000rpm in 3rd at 70mph properly.

 

It doesn't do this all the time, only sometimes. On my recent 900 mile towing trip I crossed the Cumberland Gap at the Tennessee/Kentucky line twice and had no trouble and ran 165 degrees trans temp. at the base and up to 195 degrees at the crest-but it came back down to 165 after the crest, but when on a very very gradual grade is when it heated up to 200 degrees and stuck there. If I pulled over and turned off the vehicle for a few minutes and then continued on, it went back to running at 165 degrees. When it does this "ride" the torque converter scenario-once the temps get up to around 200, then the transmission shifts really hard-abnormally hard and this is the only time it does that.

 

The vehicle has 109k miles and the torque converter was replaced about 2 years ago-which is 1.5 years before I bought it. I believe the trans. was also rebuilt at that time.

 

Ideas on the problem?

 

 

 

I have also posted an identical thread in the performance section to get ideas on upgrades.