engine temperature towing

gmcmax · 06-01-2007, 08:37 AM

I have a new 2007 GMC classic 2500 HD with 1500 miles. While towing my 10,000# camper in the mountains the temperature climbs to 235 degrees before the fan clutch locks up. The temp. then drops to about 205 degrees and stays there. The temp climb to 235 only last about 1 minute is this normal or do I have a cooling system/fan problem. Thanks, Paul.

**ob_1jr** · 06-01-2007, 12:19 PM

I don't know if I trust the guages on the dash to be 100% accurate, but it does seem to a bit high though. My guess would be that the guage in the cab is slightly off, but I haven't had any experience with high engine temps. I have a LB7, and as far as I know, there hasn't been a problem with overheating. Have you tested your antifreeze to see if it is the right mixture? I don't think it would cause this, but it is worth a shot. It almost sounds like the same problem some of the LLYs were having. BTW, welcome to the site!

John-Boy 331 · 06-01-2007, 05:47 PM

hey man, i just got a 06 lbz 3500, my temp gauge does the same thing but it ranges from 175 to 195 and thats with 25k lbs on it or empty, i've haven't had a chance to stop it for a day to get it to the dealer to check that the gauge is right, but like u said it does this pretty rapidly

**ob_1jr** · 06-01-2007, 09:12 PM

moving from 175-195 is pretty normal...I see that all the time. I believe that's when the thermostat opens.... GMCMAX, you could have a defective thermostat.

idrivebowtie · 07-03-2007, 09:54 AM

i drive my truck really hard and i never see my temp get above 195 and that is towing a #8000 punched

Jasondt2001 · 07-03-2007, 01:53 PM

It's done that to me pulling my horse trailer, probably around 13k w/ the horses.
It gets maybe 225 before my fan comes on though, just enough to make me sweat and get nervous going up a hill.
On flat ground that thing stays just under the 210 mark (the middle mark) religiously and never moves until a hill.

Happy towing and i hope this helped

06LBZ · 07-05-2007, 05:23 PM

you should see some notice in the dash info center if its a problem. the ecm's these days would alert you. engines are also running hotter for emissions reasons also. gotta love it. i wouldnt be worried though, as long as the temp comes down with fan engagement.

Jasondt2001 · 07-05-2007, 08:17 PM

The ECM will ding and tell you when you're overheating through the DIC.
it will also start to cut power when it's getting real hot I've read.

rota92 · 07-13-2007, 11:44 AM

My LBZ stays mint, towing about 14k and with a full load of people in the truck and all our crap.

Trans temp only comes up about 50 degrees over normal as well.