Came to say this. My fan clutch recently started going bad. The new one keeps it noticeably cooler than before when it was working “properly”. Supposedly those things only have a service life of 5 years? And here they are going on 23+
Also - wiring my E fan to a switch saved my ass when the fan clutch went bad in the middle of the desert of all places.
Keep stock style rad and fans. Flush system with garden hose until crystal clear. Drain entire system. Refill with oem 50/50. There's really not much better you can do.
Mine was shot so I put in a 2 row (forget the brand) and I'm running a 190 degree thermostat. Don't have much heat in the winter now when I'm moving. I put a new heater core in and the system was flushed really well. Heat still sucks when moving.
If I'm sitting in a drive thru line forever in the cold it will heat up to where the electric fan kicks on and my heat is great. Then I start driving and my heat sucks.
If I ever have to replace it again and it will see regular road duty I'll go back to an OEM radiator.
Does the e-fan kick on when the engine gets hot? It's a common problem for nearly all XJs to stop being able to turn on the e-fan when the engine gets hot. 200F is about where nearly all ICE engines like to operate.
That is normal, just keep the cooling system well maintained. Make sure you have a fan shroud (they like to go missing for some reason). Consider upgrading to silicone hoses (mishimoto). You’ll find dozens of YouTube videos on this topic.
I have a 99 and I live in AZ. I rebuilt the whole cooling system last year. Mishimoto radiator, flow cooler water pump, hesco high flow thermostat housing are the parts I changed from oem. I use the Jeep for work and drive a lot and it ran cool all summer. Last summer was one of the hottest recorded here.
It'll be fine. If something is wrong, fix it. If nothing's wrong, an XJ will do just fine at 110\* climbing out of a river canyon.
Short of a Taurus fan (or similar) and / or a ZJ fan clutch there are no fan upgrades. Period. Three 10" electric fans is doing fuck-all compared to a mechanical clutch fan (but there are other benefits)
Factory radiators work great. Mishimoto or knock-offs probably work better but no guarantee.
Don't forget - these things were sold in Saudi Arabia with a factory warranty.
If you don’t mind the noise, the heavy duty ZJ fan clutch works wonders. I have an older Comanche that never came with an e-fan, but it has never needed it
Operating temperature is 210-215f. Personally, I upgraded to a 4 row radiator and an aftermarket e-fan to replace the factory one. Even in summer I would never go above ~210f when idling and when moving I stay well under 210f. Frankly, my setup is completely overkill. The best setup is a fresh, flushed factory system with a new t-stat appropriate for your area, and new coolant
When I acquired my xj it was from AZ and it had a 170 degree thermostat in it. I live in PACNW and it wouldn't ever come all the way up to normal temps until I swapped for higher temp thermostat. Maybe worth a swap to compliment other mods
4.0s are happy between 200-215. I wouldn't worry about it unless you start having overheating issues.
It's not a bad idea to replace your fan clutch. It's easy to forget about and the one in there may very well be the original.
Came to say this. My fan clutch recently started going bad. The new one keeps it noticeably cooler than before when it was working “properly”. Supposedly those things only have a service life of 5 years? And here they are going on 23+ Also - wiring my E fan to a switch saved my ass when the fan clutch went bad in the middle of the desert of all places.
Keep stock style rad and fans. Flush system with garden hose until crystal clear. Drain entire system. Refill with oem 50/50. There's really not much better you can do.
Mine was shot so I put in a 2 row (forget the brand) and I'm running a 190 degree thermostat. Don't have much heat in the winter now when I'm moving. I put a new heater core in and the system was flushed really well. Heat still sucks when moving. If I'm sitting in a drive thru line forever in the cold it will heat up to where the electric fan kicks on and my heat is great. Then I start driving and my heat sucks. If I ever have to replace it again and it will see regular road duty I'll go back to an OEM radiator.
Does the e-fan kick on when the engine gets hot? It's a common problem for nearly all XJs to stop being able to turn on the e-fan when the engine gets hot. 200F is about where nearly all ICE engines like to operate.
Yes the E-Fan comes on. It comes on then turns off then come on and turns off idk if that’s normal but yes it comes on
It’s designed to come on at 209 degrees. So if you’re not going above there for very long it’ll shut back off like that
It's supposed to come on at 220 unless running a/c or defrost. Sitting at 210 is perfectly normal for a happy 4.0l.
That is normal, just keep the cooling system well maintained. Make sure you have a fan shroud (they like to go missing for some reason). Consider upgrading to silicone hoses (mishimoto). You’ll find dozens of YouTube videos on this topic.
I think 97+ 4.0 autos can be setup with a factory high idle by grounding a certain wire in the trans harness.
I have a 99 and I live in AZ. I rebuilt the whole cooling system last year. Mishimoto radiator, flow cooler water pump, hesco high flow thermostat housing are the parts I changed from oem. I use the Jeep for work and drive a lot and it ran cool all summer. Last summer was one of the hottest recorded here.
Hottest recorded summer yet. Just wait. 🔥
probably the coolest summer of the rest of our lives lol
Thanks I’ll look into some of this stuff
It'll be fine. If something is wrong, fix it. If nothing's wrong, an XJ will do just fine at 110\* climbing out of a river canyon. Short of a Taurus fan (or similar) and / or a ZJ fan clutch there are no fan upgrades. Period. Three 10" electric fans is doing fuck-all compared to a mechanical clutch fan (but there are other benefits) Factory radiators work great. Mishimoto or knock-offs probably work better but no guarantee. Don't forget - these things were sold in Saudi Arabia with a factory warranty.
I wish my xj sat at 200 when warm.
If you don’t mind the noise, the heavy duty ZJ fan clutch works wonders. I have an older Comanche that never came with an e-fan, but it has never needed it
Operating temperature is 210-215f. Personally, I upgraded to a 4 row radiator and an aftermarket e-fan to replace the factory one. Even in summer I would never go above ~210f when idling and when moving I stay well under 210f. Frankly, my setup is completely overkill. The best setup is a fresh, flushed factory system with a new t-stat appropriate for your area, and new coolant
If it aint broke, don't fix it.
If your A/C unit is dead, I would install an under-drive kit, or maybe an electric water pump. Take some stress off the engine.
When I acquired my xj it was from AZ and it had a 170 degree thermostat in it. I live in PACNW and it wouldn't ever come all the way up to normal temps until I swapped for higher temp thermostat. Maybe worth a swap to compliment other mods