6.0 Towing in the Heat, any suggestions?

[JollyBowtie]

Just a random question for everyone...My uncle has an 03 or 04 1500HD with a 6.0, crew cab 4x4. He pulls their fifth wheel trailer with it. I think he said they make a rock solid 7 mpg towing, which compared to the 91 big block 4 door dually they had years ago, he is impressed. Something he said got me to scratching my head though. He was telling me that when the temperature is, say, 85 degrees, it tows like crazy. Good power, acceleration, the whole nine yards. He said if the temp is over 95 or so, the truck is completely gutless. He said the temp makes a night and day difference in the power the truck has pulling. Just wondering if anyone else has ever noticed anything like this, and if you were able to do something to overcome this issue. I am trying to talk him into a PCM tune, and I think if I ever get my 4.8 done, it might convince him (He has had some 4.8 company pickups, so he is no stranger to their lackluster performance). I am wondering if maybe there is an air intake temp issue that could be overcome. I don't think he has had any problems with the truck running hotter in the higher temps. Just kind of tickling the brain over this one.


ROb

[TiredFarmer]

Never noticed any difference in my 6.0 but I was always focussing more on tranny temp guage than if there was any difference when cooler/warmer outside. I am assuming that these indications/observations were done at same elevation? Might want to have him clean the air filter and box.

[Stratosman]

Getting it tuned is such a great bang for the buck anyway, I'd tell him to have that done first and see if it makes a difference.

Could the computer be screwing with the A/F ratio at a certain temp causing the issue? I have no idea, just thinking out loud.

[JollyBowtie]

It is the same trip, same fifth wheel most trips. I have noticed a difference in cooler temps with my old carb'ed pickup, but that is to be expected. I have never noticed that much of a difference in a fuel injected vehicle. Apparently it is a drastic difference. Just a good head scratched I guess.

ROb

[Stratosman]

Of course cooler temps yield more power, but not 85 vs. 95 :think: