Hello - New to forum
Fighting this nagging issue when my truck hits an extended incline which is easy to do in AZ lots of mountains here the temp shoots up. I have replaced the Fan and radiator with a 3 row radiator with dual electric fans as well as a new water pump and thermostat 180 degree fully deleted truck running a stock tune. Still heating up but as soon as I level off or drop down a hill temp immediately goes down to normal around 200 +/- 5. I am not having any signs of a blown head gasket no oil in water or vice versa. Not using any coolant up either. I bled the system just to make sure there is no air trapped amd nothing. I can only think of a last resort bleed down test or pull the head off.

Any suggestions are appreciated since this is my first diesel.

 

Can you be a bit more specific about "heating up"? Are you saying that the truck is overheating? How high does the needle on the temperature gauge go? Into the red or just a few needle widths higher> Don't forget that when the engine is working hard ie climbing a hill, that the temperature will also climb a bit but then stabilize.

 

245

 

About the only thing that immediately comes to mind is the thermostat. You said you replaced it, but was it an OEM thermostat or aftermarket? Seem to remember threads from the distant past where aftermarket thermostats caused occasional overheating and replacing that with an overpriced OEM thermostat fixed the overheating problems.

When you eventually rectify the problem, please tell us the cause so that we can all learn.

 

I wonder how it ended up ?