I believe the OP was just trying to be helpful, not ruffle anyone's feathers... take it easy on him..

 

wow then my motor should be blown up by now.

 

~205 is normal on these XJs and they are meant to run that temperature from the factory. You shouldn't have a range of temperature readings like that as the thermostat regulates that. If you're running a wide range like 140 tp 210 I'd suggest that your thermostat is stuck open. BTW, my '99 XJ ran the same ~205 temperature as my current 2000 XJ when brand new. ~205 is what you want and an indication that your cooling system is function properly as intended by the factory. It should reach that temperature rather quickly and stick there with a few degree change while running down the road. People do run cooler thermostats, but I'd suggest running a factory Mopar unit.

 

with my setup and these cooler temps it takes me about 10 miles before I have to turn the blower down.

 

Mine runs High Mileage Synthetic oil since 100k.. at 177K I got 10k miles and the oil is still clean! Stuffs amazing.. Its the only fully synthetic for high mileage I can find.. You should use it now while your on a fresh start

 

I bought my 2000 Cherokee Sport new in 2001. During the test drive I questioned the temp. ga. sitting on 210 all the time. The sales guy said that is what is was set up for and it has always run like that.

If it climbed just above 210 the electric fan would come on and the temp would drop back to 210.

These days the engine is well broken in and operating smoother/easier than ever.

 

OMG...another thermostat thread...

Worth considering that the t-stat measures temp at the t-stat...it's hotter in spots like cylinder jackets, etc.

And, again, the internal parts are designed to expand a calculated amount at a specific operating temp and oil is designed to lubricate at that specific op temp...and the standard op temp for ordinary internal combustion car engines is 210 degrees. This is the average temp of the coolant (and perhaps the oil, too) when the specific parts (like piston ring, rod bearing, etc.) are at the correct temps not the part itself.

 

When mine gets hot everything starts to screw up like directionals and runs worse.. The colder the better LOL.. If I can get this to sit at 195 degrees can it hurt the truck? I want to put in a lower temp unit.. I could care less if Im freezing in winter..


These trucks run HOT to begin with if you ask me

 

Its not wise to run the motor cooler for reasons CAEMI stated. The motor is made to run around 200 degs so thermal expansion makes a tight fit on the bearings and what not.

 

If 210F is the mythical, magical, perfect, doomed-if-u-don't coolant temp number, then I wonder why Chry/Jeep/Mopar offers a alternate 180F t-stat for the XJ at the dealer parts counter?

 

cheap fix to the crappy rad they installed in the XJ?

 

Both of my Jeeps, WJ & XJ run at 210 with 195 T- Stats and I never had an overheating problem!

 

Not to be a dick but just because they offer it doesn't mean its right.

Mitsubishi offers both kevlar and non-kevlar based timing belts for their 1g and 2g Eclipses. Everyone knows the kevlar ones are better, stronger, and last longer, but the non-kevlar belts are still offered.

 

Guess the engineers figured 180F and non-kevlar would both work and be acceptable.

 

Acceptable and correct are two different things.

As experienced as you are I'd think you'd be very familiar with the differences.