I know I know another cooling issue thread I searched

When driving at low RPMs and sitting at an idle it will run warm. If I throw into neutral and rev it up a few times it will drop down to around 225.

Heres the deal. I wanted to replace the fan clutch because I was told it was bad out on the trail one day. It was running right at 210* but I had my doubts about it after it overheated on me in the desert while in some soft sand.

I installed the new fan clutch and while I was at it I put in a new Tstat (195*). This is when I started having this issue. I thought it may be air in the cooling system. I "burped" it even though its a '96 and shouldn't require it. Still no good. Took it in and had the cooling system cleaned and flushed. Same problem. The new fan clutch seems to spin more freely than the old one when it is at operating temp.

At this point I am thinking it may be the water pump or a bad fan clutch.

Just wanted to hear some opinions.

Thank you.

1996 4.0L NP231

 

try to free spin your fan clutch, if there is drag then your fine, i think your on the right track with the water pump... maybe also a clogged/slightly clogged heater core.