Help: 2001 duramax overheating issue

[ecc_33]

My uncle called and said his 2001 crew cab dmax is overheating. Truck has alittle over 100,000 miles and has built suncoast tranny that is about 220ish* and the engine climes sky high at anything over 65mph. There pulling a 8,000# boat through new mexico right now on there way back to ohio. Truck has a 90 edge juice box and straight pipe exhuast....Has boost leak thats not fixed, Clean air filter, No signs of water leaking anywhere, Full of fluids, From what they know the radiator is clean, Just keeps getting hot and then cools down rapidly when going down hills. Any ideas? Thanks, Eric

 

[bullfrogjohnson]

could be blown headgaskets with hot combustion gasses going past the temp sensor. Is there soot in the coolant?

 

[03 D-max]

water pump mine was doing pretty much the same thing when i had to replace mine

 

[Big Block 88]

does he have gauges? What is the boost and EGT doin? I am kinda leanin toward water pump too.

 

[CancerPipe]

My water pump only leaked when I was moving. Any pressure at all in the cooling system?

 

[Stingpuller]

Maybe the boost leaks

Tell them to turn the edge off so it wont add any fuel. If it's adding fuel and no boost it will heat up. The cooling system sounds like to me that its working if it cools down going down hills. Jeff

 

[ecc_33]

yeah edge was removed. It ended up being a dirty radiator. He blew it out at a truck shop and worked great from there. Never went over 190* and Ac started working..Amazing what a clean condensor will do.