I will make it as quick as I can -
I have a 2005 Dodge Ram 1500 with a 4.7. It started running hot - so I started working my way through the system. Ended up with a new radiator - fan clutch - water pump - thermostat - radiator cap. Still ran hot.
One day it ran so hot that - by the time i got off the road - it would not start. so now a have a reman engine in it with 3200 miles. (Had 114K when i put the new engine in)
So - in replacing the engine they guy took off the a/c compressor. i just got the a/c charged yesterday - and now the truck is overheating again - unless i run the heater.
If I understand correctly, you had no overheating with the A/C removed? And is that with the compressor OR the compressor belt off? Then with it reinstalled the overheating comes back? If so, I'd look at the clutch on the compressor to be sure it is engaging / dis-engaging properly and not creating excessive drag.
when all of this started - it got to a point where i had to run the heater all the time to keep it from overheating - then it got worse. so it seems like im at that stage again... just waiting for it to get worse. Also check your idler pulley, any drag on the pump drive can cause these kinds of problems.
What could be causing it to overheat? i burped it yesterday - and could see the coolant moving in the radiator. the radiator does not have any cold spots. one odd thing is when it does get hot - and i have to turn the heater on - it does not really seem very hot. sometimes the heater is extremely hot - but not when the truck is running hot.
anyone want to buy a truck with a new motor? ....cheap