I don't know if this is normal or not but when I am towing a 24' travel trailer up long grades (like over Donner Pass on I80) If I keep the accelerator almost to the floor to maintain 60mph or so, my temp gauge goes to the top end of the "normal zone" (on the dash gauge). I back off a bit and it goes down some. I don't want it to go above the "normal zone" so when it approaches the the high end of the normal zone I turn off the A/C, back off on the accelerator and if that doesn't work, shift from 6th gear to 5th. The outside temp is typically in the 80's. I had the same problem with my 99 Dodge Diesel and the dealer put in a lower temp thermostate which didn't solve the issue but did allow a bit longer time for the temp to go up probably because the engine initially had a lower temp so it took longer to heat the coolant. I would think that the engine in my truck would be designed to handle near full throttle at 60 mph up a grade pulling a trailer but maybe it is not. What do others experience in this regard? I have approx 40,000 on the truck and haven't had it into the dealer for any problem and the only issue (if you can call this an issue) is this overheating. Maybe I am asking too much for my vehicle?? I regularly clean the fins on the front of the radiator every 5000 miles and keep the coolant level where it should be.

 

That does seem like it is getting hot, I tow my 30 ft trailer over mountains all the time and my gauge only goes just over the center line. I also hose out the rad and all the other coolers, does your fan clutch come on when the air cond is put on, also are you running the air when climbing hills if you are maybe shut it down.

 

I have always found that my truck runs cooler WITH the air on because it makes the fan clutch engage. Turning the A/C off will cause my temps to rise.
If you are still in the "Normal" range then I would not worry. Pulling a trailer up a grade will sometimes cause temps to rise. As long as it comes down after you crest the hill I would say it's normal....

 

Set the cruise control to about 57mph and let it go. The computer knows exactly what is needed. It may need to drop down a gear to keep things in spec. I pull a 12k 5th wheel with the cruise on all the time and have had no problems unless somone cuts me off and I have to kick it out of cruise. It can hold speed much better than I a can and the temps do't get up more that 210 before the fan kicks in on full if it needs to,
Also clean you radiator and change that nasty air filter

 

I've taken the first wife and the Fox up the hill many a time. The worst is when there is enough traffic that I can't get a good running start at a hill and have to start out at 45 or so. Even then though, it is the EGTs that I worry about occasionally, the water temp has never gotten to the top end of the safe range. Ummmmmm.... yeah, never.

Like someone suggested, you ought to look at your fan clutch. Any codes?

 

Doesn't sound like a problem at all. A bigger load requires higher power production. Heat is a byproduct of power production. Diesels tend to be a bit more efficient at higher temps. Unless you're above 225-230*, I wouldn't sweat it.

 

What are you calling the normal zone? Is the normal zone for you from the low part of the gauge to the middle hash mark? Or do you call the normal zone from the left hash mark to the far most right hash mark? My truck has never gotten but a little past the middle hash mark, which is normal. That is right at 200 deg. for my truck.

 

I am calling the normal zone an arc that has 2 hash markes at each end and it goes from approx 10 to 2 (in relation to a clock). In the middle of this line the gauge says 200 and beyond the end of this line there is another hash mark that has 245 under it. I am referring to the high end of the normal zone is where the needle is at the 2 oclock position

 

If your truck is moving all the way over to 245, then something isn't right. Have you ever weighted your truck and trailer before your trip? I would be interested in how much weight you are at. Your engine fan should be roaring like crazy at this temp.

 

Id try dropping into fifth and see if that helps. Youll be pulling more PRMs (obviously) but you wont be flooring it.

 

I'm not all the way to 245 (Which is out of the normal zone). I am at the very end of what I referred to in a couple of previous threads as the end of the normal zone. If I kept going 65 in 6th and continued full throttle, I'm sure it would peg at 245 but I back off, slow down and go into 5th gear to keep it in the normal zone.

 

My truck and camper weigh approx 10,500. I don't really hear the fan "roaring like crazy" but I'm not really listening to it. By the way, thanks for all you guys suggestions and ideas. What I'm really trying to find out is: Is what I am experiencing normal. Considering I had the same issue with my 1999, I'm thinking it is normal and the truck's cooling system isn't designed for fullout operation in hotter weather with a heavy load. I guess the load doesn't really matter as long as I am asking the truck to go max throttle. Just that with the heavier load I will go slower.

 

See??? that's the thing. It isn't something you would be listening for but it is something you would notice as an out of the ordinary loud whirlwind noise. Unless you have a hearing deficiency, you should notice it kick in right away, each and every time. Check your fan clutch, you will probably find it not working so well.
Back to morning brew...

 

An old rule of thumb with big trucks, heavy loads & grades was: "drop to a gear in which you can still accelerate going uphill". While temps of 220F don't worry me, I'd still rather drop a gear and get up the hill at 52 versus 62 if I think it will be easier on the truck.

 

I checked mine the other day and towing about 9k my gauge goes between 195f to 210f never more never less, even empty running temp is right at 190f I am kind of **** at keeping my coolers clean, at the end of every day towing I will clean the bugs and crap out of the coolers.