temp rises while towing

[rikkip]

I have a 99 F350. While towing my trailer and at speeds of 75 mph and over the temp rises. If I let off the speed the temp comes down. Does anyone know why this could be happening?

 

[Wingdog]

How much weight were you towing, how hot was it, air conditioning on, and were you going up hill? These things all come into play with the motor heating up.

 

[JLDickmon]

well yeah!
load = heat
How much did it rise, and
when was the last time you looked inside the radiator?

 

[rikkip]

About 3500 lbs. Not quite in the red. The air was not on. No hills . Also I have my trucked serviced every 3000 miles so my radiator has been looked at recently. I have always pulled a trailer with this truck and have never had this problem before.I am a woman and do qiute a bit of traveling alone so I was just trying to find out if it may be leading up to something serious. Thanks for your help.

 

[Tbar]

How does the cap on the degass bottle look??? Do you have white residue on the back side of the tank under the cap?

If so a new cap might be in order.


Tbar

 

[Wingdog]

3500 lbs is a walk in the park for a SDD. Possibly a stuck thermostat.

 

[iracemine]

welcome to the forums, and +1 for the stuck thermostat. possably sand in there.

 

[jobaa]

i had a similar problem. changed the fan clutch with no results. sent my radiator out to have it cleaned out. it was about 60% clogged. truck had 240,000 miles. you can't see the clogged tubes by looking into the radiator. it has to be taken apart. the radiator shop told me that cleaning out the aluminium core will eventually result in pin holes developing. i drive a lot in the desert in temperatures well over 100 and i don't need problems. bought a new radiator. problem solved. i think it was money well spent.