One could probably count the number of threads on one hand that say "I've replaced the radiator, water pump, t-stat, fan clutch, rad cap, hoses and flushed/re-filled the system with fresh coolant".

If it still overheats, after eliminating the guesswork with new parts and service,.......don't go uphill.

There seems to be hundreds of threads saying "I replaced my radiator cap but still overheating...what could it be?".....really?

 

Whoever thinks a rad cap will solve their issue shouldn't even drive anymore.

 

Just a thought here...

Since it only occurs going uphill which makes your transmission work harder. And since by default you trans cooler lines (whether you have an aux cooler in front of the radiator or not ) are ran to a cooling reservoir that's in the cool side of the radiator tank. Could your trans fluid be heating you engine coolant.

Again just a thought as you probably need a new water pump anyways. But if it only occurs uphill....?

 

U've replaced the t-stat and flushed the rad and we presume u've replaced the rad cap (LOL)......hum, don't drive uphill or longer than 30 seconds....... until u've replaced the radiatorand the water pump .......then the system will be new and if it still overheats a couple of months from now, may want to rethink the 2 efans and replace one of them with the OE mechanical fan and a new fan clutch.

Unless u know the OE stock fans cfm rating AND u know ur current dual efan cfm rating is equal to or higher than stock, u may have some serious overheat issues in the AZ summer heat.

The cooling system (water pump) will never know if ur facing uphill or down.

 

I never said the rad cap solved the issue or would. I haven't even din the rad cap yet because it's still holding 16psi. The dual electric fans in my jeep are OEM. When I took it to the jeep mechanic and mentioned puting a mechanical fan in it and he said that they were actually the OEM dual fans that were an option.

 

I do have an aux cooler in front of my rad I believe.

 

U misunderstood ur mechanic or he misunderstood OE standard cooling vs OE heavy duty cooling. Standard OE cooling consists of 1 mechanical/belt driven fan.....OE HD cooling has 1 belt driven and 1 electric fan. The OE belt driven fan will pull more cfm than the OE efan so if u have 2 OE efans, airflow thru the rad has been reduced.

 

This guy knows what he's talking about. I agree with everything. The OEM mechanical belt-driven fan would work better for you than another OEM electric fan

 

The only place I've seen reference to using 2 OE efans is over at Novak Conversions (XJ V8 conversion).......and that's ONLY when using their big ***** radiator would 2 OE efans be acceptable.

 

I didn't take a second OEM e-fan and place it next to the original OEM e-fan. What I said was its a dual fan (one unit) that the mechanic said was OEM.

 

I just double checked. Yeah it's one whole unit with a Chrysler logo in the middle.

 

Chances r, it's from a Plymouth Horizon or some other small FWD Chrysler product but it's NOT OEM on the XJ. Again, without knowing CFM airflow numbers, u just don't know if it's at least up to the original CFM rating. The OE XJ radiator is small @ 1.27 sq.in./cid and needs major air movement thru it to shed heat, especially in the extremes that AZ heat can throw at it.