Yesterday I was towing about 7000 lbs from my house to my shop, about 18 miles. It was pretty hot in Colorado yesterday and was at least 95 when I left the house. I noticed after the truck hit regular opperating temp the fan was coming on A LOT. I've towed much more weight than this in the same weather over Vail pass and Eisenhower and don't ever recall the fan coming on this often or for this long. The only difference being I was running the the AC the whole time yesterday. After I got to the shop I opened the hood and the radiant heat seemed very excessive, I touched the intercooler tubes and they were really hot (almost too hot to hold your hand on for more than a few seconds). I also noticed a small loss of power. A friend of mine said the intercooler can "heat soak" and lose most of it's usefullness and cause the EGTs to go up and the engine to get hot. Is this true? Does anyone else have this problem or is it even something I should be concerned about? Another point that might be of importance is I have an exhaust brake and used it three or four times but I don't think that should effect the engine or intercooler temp. Edited by: Crawler Hauler

I doubt it was 95 degrees over Vail Pass though. When it's that hot outside, your truck isn't going to run like it does at 70. I had asked the same ? a few weeks back, and the consensus is that when it's hot outside, the air is not as dense and your engine is not making max power. Aircraft suffer from density altitude and so do our trucks. I wouldn't worry about it.

It wasn't 95 on Vail pass, about 85, but it is on the plains and in Grand Junction when I get there. I understand the air density thing but it never did this too me last summer. Just seems extremely hot for something that is supposed to cool things down. I ran it real hard with the AC on today today at lunch (89 degrees) to try to get it to do it again and the intercooler tubes are fairly cool when I shut it off. I'll try it again towing and see if that's the cause. I must be paranoid.

How fast were you pulling that 7K pounds? If you were running 75+ you were using a little boost. More boost = more heat. Later! Frank

I do not know about engine problems or intercooler problems but when towing only 3000 lbs at temperatures above 90 degrees, above 60MPH and above 4900 feet elevation, my fan runs almost non-stop. Noisy pig.


Edited by: Bronco

I find if you run the AC it adds heat into all the cooling systems. My truck has never been that hot but maby I have never worked it that hard on a hot day.

I ran around South side of Denver on Sunday pulling a horse trailer ( 10K+) the fan would kick in accelerating up hill but it did not seem excesive. I had full a/c on. The horse show I am at is at about 6300 ft. http://www.dieselplace.com/forum/smileys/Ermm.gif

My recent trip took me across the central valley here in California and from Fresno up to 7,500 feet in the Sierra's pulling my 9,000lb fifth wheel. Temps were 90+ going there and 100+ coming home. The fan ran quite a bit and I never, ever shut off my A/C!!!!! I like staying cool!!! Never thought to grab hold of the intercooler. I'm sure anything under the hood has to be pretty warm working it this hard.Edited by: BigdaddyG

i was running 5k from 8000ft down to Boise...fan started to run regularly when I hit the interstate straightaways. Temp was mid 80s and had AC on...only thing I did was that since this was the most fan clutch usage I heard since I bought was engage tow/haul and take my time going thru town and letting it cool down a bit. If you didnt use t/h you might have built up a little heat in the tranny and the intercooler was just hot from that...? Just a thought. Edited by: tswartos

I wasn't even towing anything yesterday and my fan was on almost constantly in Aurora, CO. Can't wait to hear it on the tow down to Pueblo this weekend. Oh well, at least it keeps the mighty d cool...

Glad to know it's normal. I'm probably just paranoid like I said. Thanks for your info guys.