Hey vegatank6,

Welcome to the forum and count yourself lucky to have a montero. It's one of the most underrated 4x4s in this part of the world.


I am more inclined to think you may have a bad mechanical clutch on your fan since you are only getting warm at slow speeds/stopped. Its a viscous fan. when engine bay is hot, the fluid thickens somehow and the fan will have some good resistance in turning. Spin with your hand, it should stop no more than 1/4th turn after you take your hand off it.
When engine is cold, the fan will have less resistance and spin more freely.

If you haven't done so already, go to mitsubishilinks.com and get yoyrself a copy of the FSM. You will find the exact test procedure for the fan.

If it does require replacement, I don't recall it being very expensive, < $50, when I had to buy one from auto parts place. Check rockauto.com as well.

Good luck.