Ford F350 Gone Mad / overheating issue

[NRBrick]

I recently purchased an 03 F350 with the 6.0 power stroke. This truck runs fine at under 40 MPH, but when accelerating beyond this point it heats up. And when you pull over before you can get the hood open it cools right back down. Checked the radiator pressure and its not building additional pressure as I am told it would if it were a head gasket. Thermostat is opening and functional, pump appears to be fine and the coolant level has not changed. NO ONE SEAMS TO KNOW WHATS GOING ON………….sheesh.

Any help anyone can offer would be great help.

[blackjudas]

I just went through this.

My truck would overheat like yours, what it was was the system needed a good flushing. Plus the fan clutch was bad. The tech said that the coolant was quite gunked up and the water pump seal was bad, though not leaking?? Anyway I wasn't getting heat in the cab etc etc, he fully pressure flushed it and it took away the symptoms.

The issues that were addressed at the same time were, glow plug module, maf sensor, water pump, power steering pump, fan clutch, fluid flush. Hopefully that may give you some ideas as to where to look?

[f350powerstroke]

im no tech but after reading these boards for a while i have a feeling ur egr valve/cooler or oil cooler my be the culprit. is ur truck programmed? u tow daily? is it straight piped?