Coolant Temps

[silvdur]

My Coolant temp is going up to 240* and cooling fan is engaging frequently.
Ambient temp 85*F
Towing 8,000# 5th wheel trailer
Is this temp increase normal? Y/N
Areas to look at for possible problems?
45,000 miles on truck LMM

[rapidoxidationman]

Seems pretty hot. Hot enough that I'd be looking into whether the cooling stack is clogged with bugs/birds/hay/pollen/whatever else can get between the A/C condenser, radiator, transmission cooler, and intercooler. A member not long ago discovered a bird's nest between two of the components that were making his engine temps soar. He had to physically take the stack apart to properly inspect it.

[silvdur]

I will check the cooling stack. Nothing is obvious just looki g at the front. I will remove the cooling stack top cover to see if anything stands out. Truck is fine not towing at 205-210. Towing I get temp surges to 240. Fan engages a lot....

[silvdur]

I partially inspected the cooling stack and found a bunch of junk between radiator and inter-cooler.
Is there a recommended way to gain access between these items?

Note: The Tech 2 tool indicates 85*C which equals 185*F
Dash gauge shows 210*F / OFF 25*F or quarter of the gauge....

[silvdur]

I finally go around to cleaning the cooling stack; what a job...
Same indication on temp gauge after cleaning.

[rapidoxidationman]

Seems like there's a way to test the sweep of the gauge. I suppose I'd also be inclined to test the temperature sensor that the gauge reads by pulling it out and putting it in boiling water. Adjust the known temperature of the boiling water to whatever altitude you're at and compare that known temp to what the gauge reads. Then you'll know if your gauge is bad or if your temp sensor is bad.