Ive tried the 180 tsat and the 160. I noticed a few things that really made milage suffer. went from 19 city to 14 on the 160 and with the 180 it was at about 16.7 average. that was before I changed out the rad for the open 3 core system and replaced the water pump and thermostat housing. Now for the most part im at about 17 city and my temp hangs at about 195 without the aux fan kicking in when its about 85-90 degrees outside in stop and go. have the 195 stat in at the moment and dont plan on changing it again.

 

Sounds good Bishop. I too have a properly functioning cooling system. I have a new stock radiator, a very complete flush, new AC condensor (for what that's worth), new 195 thermostat, water pump with 42,000 miles on it, completely new and properly mixed radiator coolant and I never even get up to 210. I average 17.8 mpg overall on the driving I do. I don't live in a city so it's not a lot of stop and go but not much highway either. I will have to check it on a 100% highway run one of these days. I am glad mine functions as designed.
Mike

 

I live in Miami its pretty hot year round. I drive mostly city and was wondering with T-stat is better the 195 or 180?

 

195

 

When ever a topic is posted. The OP needs to ask the person replying. How many cars have you owed and have you tried it? Judge their reply to those questions.


With that said. Remember, the t-stat only opens at 160 or 180*. It doesn't fully open until 15-20* after that.


Also, when people reply, some live in a cold climate. While others are in a warm climate. This makes a huge difference.


The Cherokees run at 210* due to poor design. NOT because "something" tells it to run at 210*. Period. Poor radiator and poor ventilation design. The t-stat design is to keep the coolant at a certain temp longer. Most of the "theories" above are flawed. Not all. Most. If you take the t-stat out completely, it will run very cool. 140-160*.


Most PCM need to run at 177* So, a 160* at normal climate fully open is approx. 180*. Now, factory in the poor air ventilation of the Cherokee. You can add another 15* putting you at 195*? That's why a 195* t-stat on a Cherokee result in a 210* temp on the gauge.


As for poor fuel economy. If your temp is passed 177*. You're fine!!


I know the topic is old. But, wanted to post some facts that were missed in case someone does a search.

 

The jeep runs at 195-210 because it's the way it was designed to do in order to meet EPA standards for emissions.

The reason you don't install a colder t-stat into a 4.0L (OBD1 or 2) is that the PCM will not switch from Open Loop to Closed Loop if it does not see the higher temp.

The FSM for the XJ does a great job of explaining this.

00-01 cylinder heads were redesigned to speed up the warm-up (Read: Open Loop) and get the vehicle into Closed Loop faster (Read: Reduced emissions).

 

And a person that has only owned 1 vehicle is somehow not qualified to answer a question because they have only owned 1?

What if it's a 27 year old Master Mechanic that has owned 1 vehicle since he got got his drivers license at age 16?

 

Holy open up an old thread, Batman...... , just kidding.


Dayum!......I think the theories are still flawed. If u use a accurate aftermarket temp gauge, I doubt u'll see 210 most of the time, even when using a 195 stat....but there will be some times u'll see temp readings above 210 even if u take the stat out. Would we even have these threads if the factory Jeep gauge only had a "C" and "H" and the needle usually pointed +/- the middle, like most other factory gauges?

The t-stat does one thing only.....determine minimum coolant temp. The rest of the cooling system components, their condition, and driving/operating conditions determine coolant temp above the stat rating/open temp. Think about it......why would coolant temp reach 210 in freezing cold weather, while running the heater, even with a 195 stat installed? In order to achieve best mpg's, most PCM's need to see when the O2 sensor(s) reach +/-650F, not when coolant temp reaches 177F, in order for the motor to begin running at it's leanest/cleanest/best mpg's.



When a scan tool is plugged in, u can see "the loop" go from open to closed in less than a minute after cold start-up. The loop "closes" when the heated O2 sensor(s) reaches it's operating temp which is well before coolant temp is anywhere close to the stat rating. We run a 180 stat year round, get good mpg's and the loop closes just as quickly with a 180 as it does with a 195, according to the ScanGauge.

 

[QUOTE=CrawlerXJ;2778359]When ever a topic is posted. The OP needs to ask the person replying. How many cars have you owed and have you tried it? Judge their reply to those questions.


With that said. Remember, the t-stat only opens at 160 or 180*. It doesn't fully open until 15-20* after that.

this is


Also, when people reply, some live in a cold climate. While others are in a warm climate. This makes a huge difference.


The Cherokees run at 210* due to poor design. NOT because "something" tells it to run at 210*. Period. Poor radiator and poor ventilation design. The t-stat design is to keep the coolant at a certain temp longer. Most of the "theories" above are flawed. Not all. Most. If you take the t-stat out completely, it will run very cool. 140-160*.


Most PCM need to run at 177* So, a 160* at normal climate fully open is approx. 180*. Now, factory in the poor air ventilation of the Cherokee. You can add another 15* putting you at 195*? That's why a 195* t-stat on a Cherokee result in a 210* temp on the gauge.


As for poor fuel economy. If your temp is passed 177*. You're fine!!


I know the topic is old. But, wanted to post some facts that were missed in case someone does a search.[/QUOTE

this is what a post should look like. Thanks for your input good sir. I just put in a 180 (best therm I could buy- think about what it does), new clutch fan (change with your water pump) and new pump-

i drove highway and checked my mpgs and I'm getting the best I ever have- and that is WITH a brand new roof cargo box installed: 16.858 mpgs. I don't really know shlit about cooling systems but I now know how to work on mine- and I challenge you to take what you want from this post. I'm at almost 17 mpgs and I used to be at 14-15.

Cheers peeps and don't forget to wave at your fellow XJ ;-)

 

i notice that from - 10 in winter to 90 in summer my gage reads the same after about 3 miles.? once warmed up the engine makes plenty of heat to keep i t at even temp. so the design must be ok huh?

also noticed a lot of dissagreement here without insults or name calling , finally some politeness!
i stick with factory specs.

 

i have a 180 thermostat in my cherokee and i seem to have no problems but mostly i dont feel like tearing the housing apart to change it because why change it if its working but for me it still runs at 190 and above anyways in florida lol.

 

This the second time this thread has been resurrected from the dead. For god sakes, let it Rest In Peace.

 

i read every new post. old info is good/better than new!

 

 

sigh