I am having the opposite problem, in -5*C temps mine temperature guage will hit 95*C(200*F) with no load, no front covers. Any small incline and the temp rises. Coolant has been changed along with the thermostat. Clutch fan has also been changed, but no change on temp guage. So the question is what do I check/change next? Is it a sign water pump on way out or getting weak if possible, engine temp sensor going bad? dealer has no idea. hey Truckman maybe we can combine the two trucks, raise your temps and lower mine. Also can low feron in ac cause the clutch fan not operate properly?

 

No....low freon won't affect the fan clutch. Couple of things to check. Make sure there is no air in your system, and have the radiator cap checked. If there isn;t the proper amount of pressure in the cooling system, that can cause it to run hotter. It would be nice if you had access to a scanner to read some data. If you did, you could compare the coolant temp that the ECM is seeing to that of the guage. IIRC, there are two different sensors.

 

with the cold weather- last night was 32 outside, it goot up to 200 on my 20 minute ride home. i didnt get on it or anything. i did leave the air/heat off the whole ride home. wonder if that had anything to do with it. for some reason my truck has been running right around 200 no matter how cold it is outside. i have plenty of antifreeze..

 

Plenty of antifreeze as in cold weather protection, or full of antifreeze? The next easiest thing to do is change the thermostat. Very easy to do. Just make sure to get all the air out of the cooling system. It takes a little while to "burp" the air out of it. Just keep the cap off until the thermostat opens, then fill the radiator and put the cap on. Then fill the overflow bottle to the full hot mark, and you should be good to go.

 

I was having the problem before, changed thermostat, used premix antifreeze from cummins, still have same issue. I need to check rad cap like you suggested though, maybe replace it.

 

That would be the next thing. ( the cap that is ) Then make sure the radiator is clean ( in the fins....no debris ) , then I would get a scanner involved. There may just be a problem with the sender. Does the heater work o.k.? If not... might be a water pump issue, but doubtful.

 

I think it should go higher then that. The thermostats don't even open til 190 degrees right?? SO that means there is no coolant flwing through the water jackets until it opens. It was 9 degrees out side tonight and my truck was sitting between 190 and 196 the whole way home. There may be a possibility something might be wrong it just might be your truck runs that cool. I guess every truck is different.

 

Truckman0097 sorry for hijacking your thread.
vzdude, had the rad cap checked, works properly. I need to presurize the system and see if I have a leak some where (pump maybe). Also need to get a scanner and check temps that way also. thanks for info and any other ideas you may have.

 

as in its full.

 

No worries - hope you get your problem solved, feel free to keep posting and let us know what it turns out to be.