I have a 2003 5.9l dodge ram 2500 l6 diesel, last week the belt tenrionner pulley broke down and I lost the belt also. I did replaced the pulley with a smaller one and also replaced the belt, engine works fine until I drive through the mountain with it.
After 5 miles (8 kms) climbing the temperature starts going up, but I stopped the truck before it reaches the red on the gauge.
I have just replaced the whole belt tensionner with a new one from AC Delco and I ralized the pulley is bigger, would that fix my overheating issue or is there a bigger problem?

 

Was it over heating before 1st incident? If not I would be looking for something else not right. Fan shroud in place? clutch fan working properly? I dont think new tensioner pulley will fix your issue. Serpentine belt on correctly?

 

It was not overheating before. Fan shroud? Haven't been looking for that. New tensioner pulley didn't fix the issue as I expected. Serpentine belt is exactly as displayed on the front end of the truck by the radiator. I was even thinking about a failed thermostat.

 

Sticking thermostat, fan failing, water pump failing (the vanes can wear out and push less coolant). Don't mean to be simplistic, but have you checked your coolant level?

 

Coolant level is good, haven't checked the thermostat. Changed water pump last year and it's working good. I only experience the issue when climbing very steep road going up the mountains. One thing I realized though is that I started the engine in the morning and the fan was working but I was able to hold the fan to stop it with my hand: does that supposed to happen? or is it because the fan clutch is damaged?
Thanks for your input.

 

forgot to state also that the AC stopped working at the same time. at first when you start the engine, the AC is working fine and then after 5 minutes, the compressor started to act funny like it starts then stops and for as long as the engine is working.

 

When the engine is cold, the fan should not be 100% powered. So, stopping it by hand isn't a surprise. When the engine is up to temp though, the fan should be stiff to turn. (engine off...... you like your fingers, right?) If it isn't, replace the fan clutch. A/C is probably just low on refrigerant.

 

Thanks! I wanted to know before I purchased a new fan clutch.
I also had several error codes but I only remember those 2 P0480 and P0483. Will double check later today the rest so that I can figure out what I am dealing with.

Thanks for your inputs

 

Should explain the fan shroud thing....although I believe it was newer models. on a different forum guys had fan shrouds distorting from heat..causing poor air flow. Also you mentioned loosing a pulley and belt. Just wondered if shroud got damaged. Guess not tho. Good luck

 

shroud is ok! I double checked it and it's fine.