2003 Dodge Ram Van 2500, converted by Roadtrek. 94,000 miles. Van is running hot. Have taken to dealer several times. Have replaced radiator twice, thermostat twice, coolant flush 3 times. I live at the top of a 6% 3 mile grade and have driven this van up this hill very often during the past 10 years. In the last two years the van has been running hotter and nothing seems to solve the problem. For example, yesterday, I started at the bottom of the hill at 210 degrees and arrived at the top at the far right end of the "normal" bar and the Check Gages light came on.

I noticed the fan does not switch into a very loud mode that it used to. That lead the dealer to replace the fan (and they also replaced it with a larger farm). We are out of ideas. Hope you have some!

 

Have you actually take temperature reading with something like a laser thermometer, both at the bottom of the hill and then again at the top? It might be the gauge, the sender, or alternator voltage fluctuations that are affecting the reading, while the temperature very well might be fine.

Have you done a compression test to make sure there is no blown head gasket?

Has the water pump ever been removed and inspected to make sure all of the impellers are intact?

 

Have not used a thermometer, however van acts like it is hot (power loss, external thermometer increases in temperature--after market).

The top of the engine was overhauled last year by the dealer. Indications were all 8 cylinders were cracked. Have not run compression test recently.

I do not believe water pump has been removed--will ask.

Do you have any insights about the fan--it used to make a loud noise as the engine heated up and it does not do that any more.

I'm taking it to dealer tomorrow and will ask the questions you asked below.

Thanks

 

Fan clutch is probably shot. If you can spin the fan freely by hand then it is definitely bad.

 

It does not spin freely, but it is very easy to turn it by hand. (Done with the engine off and key removed).

 

The fan is only relevant below 35 MPH. Above that more air is being forced into the radiator due to the forward motion of the vehicle than the fan can deliver.

 

I remember for the first several years that as it got hot something kicked in and it just roared. It doesn't now. Is that irrelevant?

 

I would replace your fan clutch for sure. But that may or may not solve your problem. 6 years ago I was having where mine would creep up real hot. Water pump was replaced before I bought the van, radiator had been clean and a leak fixed. I replaced the thermostat, fan clutch when I replaced my timing chain. That still did not fix my issue. I finally determined that my radiator was the culprit and that solved my slowly getting hot issue. Seems that the radiator was clogged very badly though it looked clean through the cap opening.

 

It's relevant below 35 MPH.

 

Thank you