1998 Cherokee 4.0 with recently replaced cooling system, all new with the exception of the radiator which seems to be in excellent condition, most all fins appear to be great. 195 thermostat, new housing, new waterpump and hoses. Runs temperature-wise as expected at 195-210 depending on conditions, without towing. This Jeep doesn't have a transmission cooler, YET....

During the springtime months, the Jeep ran around 210 while towing, perhaps slightly warmer in stop-go city traffic where idling times are longer. However, now that temps have risen to 85 or higher, the engine temps are reaching mid 230's and higher, even while running 35-55 mph on the highways. All fans are operational.

These temps are verified on an accurate scan tool, and the guage doesn't disagree with what the scan tool is telling me. I'm about ready to ad a transmission cooler, and placement is my concern. Also, do these high towing temps indicate anything more than needing a trans cooler, possibly a weak radiator that doesn't dissipate heat? Are these high temps caused by something else than very hot trans fluid?

 

I can't answer your questions, but just make sure not to mount the trans cooler on those stupid plastic studs sticking through the cross flow radiator. They will eventually wear through and cause a leak.

 

I wonder what the radiator looks like on the INSIDE.......

 

The outside of the radiator doesn't tell you much. It's a shame to drain and do all that work and not swap it. 90-100 bucks for a new stock one is the best option. I would swap it and you are in pretty good shape to tow. Also check the fan clutch if you didn't do that with the other work, a weak one will contribute to overheating. For the love of Pete I hope this doesn't trigger another towing thread. The last one is still going strong.

 

When I set out to repair the original cooling issues, I was chasing down a leaky water pump gasket. Budget was tight enough where I chose to skip the radiator as I didn't have much reason to suspect it was problematic.

Budget is still tight - This paycheck allows for one or the other, and it seems that you each suspect the radiator isn't cooling as efficiently as it should. When I replaced the other items, the coolant wasn't in good shape so the inside of the radiator could be corroded.

Radiator first, then ad a transmission cooler for peace of mind, correct?

 

Yes. Good plan