I have a 02 HD 6.0 with about 140K on it, have had for about a year. Had a overheating issue while pulling trailer so I replaced thermostate and flushed radiator with high hopes. Still any time there is a long steady incline the truck begins to overheat. I have a smaller trailer weighing about 6k loaded that I also pull with my Tahoe with no issues. Ive also noticed that the trans temp gets high. I was told by a friend that the trans could be the issue, anyone had this issue and if so is there a larger cooler available, does a duramax cooler fit?

 

Hi Jnl81,

Welcome to the Chevy Forums.

Did you replace your radiator cap? It costs less to replace them than have them tested.

How about that transmission filter? Interval for them is @40K, but they often get ignored. As they start to clog, they cause a drag on the drive train.

 

my silverado did the same thing, it was the fan clutch

 

how hot is hot.. 200*-230*+ engine temp. whats your trans temp..

 

i would replace the fan clutch, just a good general maintenance.
it cycles about 10 times per mile and if you have 140K you can do the math, the old clutch has had a workout, needs to be changed out anyway.

 

i have a 06 1500hd, and the last two times i tried to pull my boat out of the ramp it barely pulled it out, it was at a creeping crawl with the gas pedal to the floor, i did put a different program in the cpu (bullydog gas saver) i have now restored the factory program and have noticed some diference but have not pulled my boat out of the water yet. any suggestions.