Uphill in High Heat

My wife & I were traveling to San Diego a couple years ago durig the summer and thought we had timed it right to climb the hill on I-8 in the cooler part of the morning. Unfortunatley, we hit in the hottest part of the afternoon and climbed the hill in 114F heat. The Ford pulled my 5th up the hill almost to the top before I noticed the heat getting close to the top (red). I have a question for the long time, expert RV'ers. With a diesel engine, what are the best ways to avoid overheating when climbing a large hill like that one. We turned of the AC about 3/4 of the way up (probably should have started that way) but just curious what other methods could be used to avoid excessive heat build up?

C Nash

Senior Member
Uphill in High Heat

It want help you in the cab but, turning the heater on full blast helps the engine a little. :bleh: Have you cleaned the radiator lately? Bugs tend to stop the free air flow through the radiator. Flush the system and be sure you have the correct amount of antifreeze installed.
Uphill in High Heat

Thank you for your response. It had also been suggested that I gear down and more or less crawl up the hill, limiting the flow of fuel into the engine. I guess my concern with that was loss of momentum. Does that also sound correct? I guess I'm looking for options the next time I find myself in this sitution.


Senior Member
Uphill in High Heat

Tom, welcome. I've done what Chelse suggested about the heater, just opened the windows all the way and undressed (almost all), ha ha. When I am pulling up long hills, in my Class A pulling car on a dolly, I just get in the slow lane and go slowly and I have not had any overheating problems. I just wave to the good folks that don't handle me going so slow, but there again, I am retired and in no big hurry. Good idea to flush and fill radiator annually on puller and clean outside bugs on radiator regulary. ;)

DL Rupper

Senior Member
RE: Uphill in High Heat

Turn your A/C off, is the best advice I can give you. Also as C Nash explained, turn on your heater. That cycles your cooling water through the heater and helps cool your system. I climbed the same hill in 2004 in about 95 degree heat and didn't experience any problem with my diesel, however, I have a 6 spd manuel and may have had a better gearing selection.
Re: Uphill in High Heat

I noticed no one mentioned putting electric fans pushing air through the radiator. We have installed them on a lot of class A motorhomes and trucks as well. The only problem that we have found is that some trucks don't have enough room between the grill and the tranny cooler (make sure you have a tranny cooler).