Is My JL Too Hot?

[silverooby]

I've recently been tracking the engine temp on my 2022 JLUR XR. It typically runs at around 230 degrees and pops up to 237 at times. This is highway driving when it's about 50 degrees outside. The local dealership replaced the thermostat, but the result is the same. The dealership's research tells me there's no guidance saying when to get concerned about engine temp, so no-one I've talked to so far knows for sure if there's a problem.
Looking for some knowledgable folks out there that can tell me whether I'm OK or perhaps what path I need to pursue to track this down.
In my mind, these temps are too high. thanks, rex

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[Opus]

That does seem a little high to me also, especially if you're getting that temperature on the highway at 50 degrees where air flow should be cool and plentiful. Do you have a large winch, lights or bumper that might be obstructing the radiator?

 

[silverooby]

Nope, no obstructions. The winch is down in the bumper.

 

[Nokones]

230 degree oil and/or water temps are not unusual temps on later model vehicles. You would be getting a warning light/message displayed, if that is the case. The computer is looking out for you in your best interest and will let you know when it is time to panic, so in the meantime, trust the computer, and just drive.

 

[Terrymo]

Maybe you are already aware that the Tazer gives you the ability to force your fans to run at 100%

• Cooldown Mode: Press ▷ + CRUISE CANCEL to turn the engine fans on High. Press again to turn them off. NOTE: When the engine is off, the fans will turn off automatically if the battery drops to 11V. NOTE: The transmission temperature will read as 249 degrees while this mode is being used with the engine running. NOTE: Only works with the engine OFF on manual Jeeps

Because my radiator split at under 20k miles offroad with no warning and I had to be towed by another Jeep 15 miles down off a mountain, I decided to install the RPM fan controller so I don’t have to constantly monitor coolant temps.

Here’s the percentages of fan speed relative to coolant temps with the controller.
Example Fan Speeds by Temperature:

195°F / 90°C = 15%
199°F / 93°C = 30%
205°F / 96°C = 50%
212°F / 100°C = 75%
218°F / 103°C = 100%

This requires you to splice into the ECU 1 harness which caused me some initial concern but I got lots of good advice and instructions here.

https://www.jlwranglerforums.com/forum/threads/rpm-exteme-pwm-controller-questions.132487/

Keep in mind the RPM fan controller once installed does not allow the Tazer forced cooldown mode to work.

—-edited the Tazer trans temp reading—-

 

[HHGadget]

Maybe i missed it but what motor do you have?

 

[wrang_stang]

I've recently been tracking the engine temp on my 2022 JLUR XR. It typically runs at around 230 degrees and pops up to 237 at times. This is highway driving when it's about 50 degrees outside. The local dealership replaced the thermostat, but the result is the same. The dealership's research tells me there's no guidance saying when to get concerned about engine temp, so no-one I've talked to so far knows for sure if there's a problem.
Looking for some knowledgable folks out there that can tell me whether I'm OK or perhaps what path I need to pursue to track this down.
In my mind, these temps are too high. thanks, rex

Mine hangs around 200-215 and that’s after driving for a while in relatively hot weather.

I wouldn’t expect more than that unless you’re towing, carrying a heavy load, or maybe in high altitude conditions where the turbo is working harder. But I also don’t have advice to give except that the car should protect itself if things get out of hand.

 

[ScotM]

And you checked your coolant levels? If it’s 50 outside and you are in a flat road at 70 mph, you should not be at 230F. I’m assuming 2.0? Mine would be around 210-220. Now it’s 200 or so with the rpm extreme controls module

 

[Aonarch]

Are your radiator fins damaged?

These JLs do run hot, but that is a bit too high, especially with 50F ambient.

My 2025 2.0T does not get that high. Maybe 220F max.

The RPM fan controller is a good idea, but I just hate the installation of it.

An aftermarket tune, like Livernois will change the fan behavior as well.

Maybe switching to the 2024 grille, or the Gladiator Max Tow grille will help as well. They have better airflow.

Coolant is 10 years 100,000 or 150,000 miles, but you might want to do a drain and fill, or even use a radiator flush treatment.

Portland gets a bit cold, but you could think about doing 60% water and 40% coolant for better performance.

 

[MauiSteve]

Where are you getting the temperature readouts from?

 

[mgroeger]

@Terrymo - My trans temp goes to 249 when I do this... not 229.

Maybe you are already aware that the Tazer gives you the ability to force your fans to run at 100%

• Cooldown Mode: Press ▷ + CRUISE CANCEL to turn the engine fans on High. Press again to turn them off. NOTE: When the engine is off, the fans will turn off automatically if the battery drops to 11V. NOTE: The transmission temperature will read as 229F while this mode is being used with the engine running. NOTE: Only works with the engine OFF on manual Jeeps

Because my radiator split at under 20k miles offroad with no warning and I had to be towed by another Jeep 15 miles down off a mountain, I decided to install the RPM fan controller so I don’t have to constantly monitor coolant temps.

Here’s the percentages of fan speed relative to coolant temps with the controller.
Example Fan Speeds by Temperature:

195°F / 90°C = 15%
199°F / 93°C = 30%
205°F / 96°C = 50%
212°F / 100°C = 75%
218°F / 103°C = 100%

This requires you to splice into the ECU 1 harness which caused me some initial concern but I got lots of good advice and instructions here.

https://www.jlwranglerforums.com/forum/threads/rpm-exteme-pwm-controller-questions.132487/

Keep in mind the RPM fan controller once installed does not allow the Tazer forced cooldown mode to work.

 

[Blacksport]

I've recently been tracking the engine temp on my 2022 JLUR XR. It typically runs at around 230 degrees and pops up to 237 at times. This is highway driving when it's about 50 degrees outside. The local dealership replaced the thermostat, but the result is the same. The dealership's research tells me there's no guidance saying when to get concerned about engine temp, so no-one I've talked to so far knows for sure if there's a problem.
Looking for some knowledgable folks out there that can tell me whether I'm OK or perhaps what path I need to pursue to track this down.
In my mind, these temps are too high. thanks, rex

They run them hot to reduce emissions, but IMO, that's too hot. I replaced the thermostat on my '25 Sport S with a 185° thermo I got from RIPP.com, JL only & 3.6 only (I think). The stock thermo is 197°, so you drop the temp 12°...it works too! Easy change, good time to replace coolant. Mopar OAT MS 90032 concentrate, 1 gal + 1 gal distilled. Disconnect bottom rad hose, drain into a big flat pan ($12 on Amazon), mix equal parts coolant & water, turn heater on when filling. RIPP calls the thermo 180°, but it's 185°...

 

[Aonarch]

They run them hot to reduce emissions, but IMO, that's too hot. I replaced the thermostat on my '25 Sport S with a 185° thermo I got from RIPP.com, JL only & 3.6 only (I think). The stock thermo is 197°, so you drop the temp 12°...it works too! Easy change, good time to replace coolant. Mopar OAT MS 90032 concentrate, 1 gal + 1 gal distilled. Disconnect bottom rad hose, drain into a big flat pan ($12 on Amazon), mix equal parts coolant & water, turn heater on when filling. RIPP calls the thermo 180°, but it's 185°...

Does the fan play nicely?

Usually you need to reprogram the fan to go along with a lower temp thermostat.

 

[silverooby]

Maybe i missed it but what motor do you have?

Sorry, 3.6 L

Maybe you are already aware that the Tazer gives you the ability to force your fans to run at 100%

• Cooldown Mode: Press ▷ + CRUISE CANCEL to turn the engine fans on High. Press again to turn them off. NOTE: When the engine is off, the fans will turn off automatically if the battery drops to 11V. NOTE: The transmission temperature will read as 229F while this mode is being used with the engine running. NOTE: Only works with the engine OFF on manual Jeeps

Because my radiator split at under 20k miles offroad with no warning and I had to be towed by another Jeep 15 miles down off a mountain, I decided to install the RPM fan controller so I don’t have to constantly monitor coolant temps.

Here’s the percentages of fan speed relative to coolant temps with the controller.
Example Fan Speeds by Temperature:

195°F / 90°C = 15%
199°F / 93°C = 30%
205°F / 96°C = 50%
212°F / 100°C = 75%
218°F / 103°C = 100%

This requires you to splice into the ECU 1 harness which caused me some initial concern but I got lots of good advice and instructions here.

https://www.jlwranglerforums.com/forum/threads/rpm-exteme-pwm-controller-questions.132487/

Keep in mind the RPM fan controller once installed does not allow the Tazer forced cooldown mode to work.

thanks, but for now I’m trying to understand whether I have a problem or not.

Maybe i missed it but what motor do you have?

its a 3.6.

 

[Pain Killer]

Has the dealer compared it to a like vehicle? Mine at 75mph Trans. temp. at 199, 201 going up hill degrees F and engine temp. is about 206 degrees F. That's in much warmer temps than you are in. I have a 3.6liter.

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