3.6 Pentastar coolant temp 222 degrees at idle

[BlackRuby23]

Is this normal? I mean, it's like 45 degrees outside and the Jeep is running way hotter than any vehicle I have ever owned. When I get on the freeway it cools down, but I'm wondering if there's a cooling fan issue or something.

Does anybody know what the coolant temp should be at idle? Do these have a 195 degree thermostat? Once it gets to 222, it will go back down to like 213, then back to 222. The oil temp climbs to 222 as well.

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[Lunentucker]

https://www.jeepgladiatorforum.com/forum/threads/temperature-reading-question.73085/post-1193196

 

[BlackRuby23]

https://www.jeepgladiatorforum.com/forum/threads/temperature-reading-question.73085/post-1193196

So I guess it's the design. Damn, I'm surprised they want the engine to get that hot.

 

[Lunentucker]

So I guess it's the design. Damn, I'm surprised they want the engine to get that hot.

It's a hot running engine. Not sure I want to pay $400 to make it run a few degrees cooler.

 

[ShadowsPapa]

https://www.jeepgladiatorforum.com/forum/threads/temperature-reading-question.73085/post-1193196

Oh, no - not that............

Totally not needed on a normally working Jeep.

Is this normal? I mean, it's like 45 degrees outside and the Jeep is running way hotter than any vehicle I have ever owned. When I get on the freeway it cools down, but I'm wondering if there's a cooling fan issue or something.

Does anybody know what the coolant temp should be at idle? Do these have a 195 degree thermostat? Once it gets to 222, it will go back down to like 213, then back to 222. The oil temp climbs to 222 as well.

No 222 at idle in 45 degree temps is not normal, normally it will run cooler while idling.
You may have a stat sticking, but there's no need to modify your truck or do anything radical.

So I guess it's the design. Damn, I'm surprised they want the engine to get that hot.

NO, it's not the design - there's a lot of misinfo there and in fact, yours has a problem. These do not run that warm idling in 45 degree temperatures.
Don't get scared or freaked out by that post/thread. It doesn't apply to you or your truck.

If you are seeing that high a temperature at idle, there's a problem.
These will run under 200 all day in cooler weather or not under load.
Don't get into that whole thing in the other thread- these don't run hot, they just don't.

Mine doesn't run that hot towing in 70 degree weather so why would yours run 222 idling? Because you need it serviced - thermostat or water pump, there's something amiss - no need to freak out and make mods or do what he did. It's absolutely not needed.

But if you want facts - if you were towing on a 70-80 degree day and saw 222 - I'd not even blink an eye.

 

[ShadowsPapa]

If you lived nearby - I'd say bring it over, we'll put aim the thermometer at it to see if that's an accurate temperature and check some things out....... but I don't see a reason to freak out at this point. Normal repairs will make it work like almost all of these do - just fine.

 

[BlackRuby23]

If you lived nearby - I'd say bring it over, we'll put aim the thermometer at it to see if that's an accurate temperature and check some things out....... but I don't see a reason to freak out at this point. Normal repairs will make it work like almost all of these do - just fine.

I'm not "freaking out," but this is a brand new Jeep with 500 miles on it. I'm not happy if there's a problem right off the bat.

 

[intentsrig]

Mine definitely starts to climb at idle. So did my JL. No air flow. On the trail it’s like that a lot. Especially my JL being it was a manual. The auto seems to run at cooler temps both idle and driving, maybe because the computer wants to keep the trans temps down so the fan runs more often?

 

[22rubi1202]

Is this normal? I mean, it's like 45 degrees outside and the Jeep is running way hotter than any vehicle I have ever owned. When I get on the freeway it cools down, but I'm wondering if there's a cooling fan issue or something.

Does anybody know what the coolant temp should be at idle? Do these have a 195 degree thermostat? Once it gets to 222, it will go back down to like 213, then back to 222. The oil temp climbs to 222 as well.

I have a 22 Rubi and mine does the same thing. Sitting in traffic during that last snow storm it did the same as yours, also did it Thursday night on my way home from work.

 

[ShadowsPapa]

I'm not "freaking out," but this is a brand new Jeep with 500 miles on it. I'm not happy if there's a problem right off the bat.

OK, it was late, I was tired, etc.
More accurate thinking on this -
A thermostat sets the minimum operating temperature.
A 195 starts to just barely open at 195 degrees. It won't be fully open until something like 220 (at least that's the old standard)
So 195 is the minimum, all else is set by coolant flow, air flow, load, and more, as far as top temperatures.
How long is it idling to get go 222?
I have a funny feeling the fans on these are set to kick in about that time.
Mine fluctuates between the mid 190s and 220 degrees while driving as a matter of course.
I've not watched idle temperatures, but then there's little idle time around here and mine shuts down at stop lights and stop signs quite often as I let ESS work so I don't have heavy traffic or prolonged idling.
I'd say if that's as hot as it gets - forget it.
If it doesn't go over that at idle, no problem.

It's possible to connect in with something like JSCAN and watch fan operation - even manually kick it on as I recall, just for experimenting.

So consider my prior as being tired and not even thinking things through.
At idle, not moving, there's no air flow and these run pretty tight control over the fan. That makes sense because running the fan is a larger electrical load, meaning more alternator work, meaning more heat generated.
Add that to the fact that 222 isn't even hot - not for any of the fluids.
If you don't get oil up to that temperature for a period of time, you keep the moisture and fuel contamination in and that means shorter oil life and shorter engine life.
You don't have to worry about coolant being too hot as far as boiling until about 260 degrees due to the pressure and the anti-freeze, anti-boil mixture.
To some extent, a hotter engine is more efficient.

 

[jav_eee]

It's a hot running engine. Not sure I want to pay $400 to make it run a few degrees cooler.

I ordered one. Living in Deep South Texas we saw 97 days above 100° last year. I do a lot of slow speed ranch driving and unfortunately lots of stop and go traffic so I want to give it all the help it can get.

 

[Pismo61]

My JKs and JL all ran hot 200ish to 225.They also warmed up fast to 195 or so.My Tacoma liked 195 to 205 and Ford Ranger likes 195 but warms up slower(Tacoma and Ranger have clutch fans).These all have the scan gauge.

 

[BlackRuby23]

Can people please post their coolant temps at idle? I first noticed this yesterday while waiting in traffic. As mentioned, ambient air temps were in the 40s when I first saw it hit 220. I pulled off to a parking lot to monitor the situation, then shut the Jeep down. I restarted and it did it again.

Being the weekend, I decided to drive home just in case something was wrong. When I got home I let it idle and watched it go up to 222 on the display, then fall back to 213, then rise, then fall back. I suspect this is "normal" for this engine, but want to verify. Once it stops raining this morning, I will check the coolant level and make sure it is ok.

Is there a scan tool out there that will allow me to monitor thermostat and fan operation from inside the cab?

 

[willys 41]

Ok. Here we go again
If you want to take control of your coolant and oil temps install the RPM Extreme JL fan controller
I did and it was one of the least expensive mods I have made and I no longer see temps as high as 235 pulling a long hill
For your information
The Maserati 3.0 v6 is the same motor as the jeep 3.6 put only smaller displacement
I have researched the temps and oil that the Maserati 3.0 v6 uses
Maserati 3.0 v6 run at 195-200 coolant temps and use 5w40
Jeep has a mandate to get the best MPG out of its entire fleet and will do what they have to to achieve this

 

[KevinC]

Edited it to reflect 2000lb trailer, not 200lb.

This screen shot is after pulling a 2000lb trailer 75 miles on flat land / 55 mph max speed; and idling for about 10 minutes.

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