Okay guys, we all very well know that xj's have a tendancy to develop overheating problems and see threads on it all the time. But see what i have here is exactly the opposite. Before i begin, I would like to say that i have an aftermarket heat gauge as my jeep came with the dummy gauges. I have no idea if i have a 195,180, 165, or whatever t-stat.
Okay, it seems that the jeep runs about at an average temperature of anywhere from 140 to 160 or so even after running for over an hour. This is without the A/C on I have no idea what it is with it on as i dont use my A/C because of the strain it puts on the engine. I KNOW this isnt a normal temperature and it ran more along the lines of 190-210 this summer when it was really hot out. What could this be? Running at this low of a temp cannot be good for my engine, as I'm sure the oil is meant to lubricate best at a normal engine temperature. If you think i should just not worry about it then i'll just let it be.


On a side note, (completely off topic) Are the taillights on these xj's made where you can replace a bulb to fix a taillight thats out or do you have to replace the whole taillight?

 

#1 add a coolant flush to your next weekends budget just to be sure
#2 put suggested t-stat in for your year xj per spec so you know whats in it
#3 the tail light housing is removable lift gate must be open should be 3 screws per housing, there is a rubber o-ring kinda thinger on the back thats kind-of a pita to line up and get in but yes they come off
good luck but you won't need it you drive an xj go for it

 

I have the same problem with an aftermarket gauge. Did you mount it in the t stat housing? Use a laser thermometer to verify the temp. Mine runs about 30 degrees above what the gauge says.

 

coolant is perfectly clean, done checked that. matter of fact i think its 100% antifreeze when i checked with the ball turkey baster thingy (cant ever remember what thats called lol)

 

Mine reads right on i think, never got above 210 idling in 105 degree weather only got to it and dropped right after

 

Mine did the same thing. before I put the aftermarket gauge on, it ran 212 or so. I changed nothing but the gauge and it began running 165-180 on the aftermarket gauge. After a month, I checked it with a laser and it was at 210 when the gauge said 180.

 

Either the thermostat is stuck open (not common but it happens) or the gauge is wrong, OR the temp sensor for the gauge is sitting in an air pocket.
I agree with the verify it with a laser thermometer. Those are just cool

 

100 percent antireezee? thats not good. Got to have a 50 50 mix for proper cooling

 

yea 100% is bad........

 

Put in a 195 degree t-stat.

 

how much is a tstat? And i remember a thread not too far back that mentioned which tstat gave you better fuel economy, wasnt it the 195?

 

your xj can run at 160 that aint to bad as long as it aint at 140 all the time 160 to 210 is okay running tempature.

 

oh yeah another thing your rig should be oiling fine as long as your oil pressure is up. 10w-30 which most of us run in cherokees, is fine at 140-160, because the W stands for winter and thats means 10 is the "weight" of the oil cold, for cold starts so it flows better, and as the temp increase the oil gets a lil heavyer. 10w is weight cold 30 weigh of it hot. so your oil is okay. so i would say run a 50/50 anti freeze mix and then a 195 t stat and call it yankie doodle.

 

It's about $6.The 4.0s like the heat.They were designed to run hotter than most motors.