06 unlimited with a 4.0

[wildbill]

hey everyone i have a question.my wrangler runs at 210 degrees water temp. all the time ,even on cold days ..is this normal?i just was wondering and is there a way to make it run cooler,a different thermostat maybe?i just bought a 17foot bantam flyer travel trailer.its running at 210 still but i'm afraid of the long grades.thanks

[Jeri Lyn]

210 is normal for an inline 6

[Davisrats]

a colder than normal thermostat will make it run worse.

210 is good.

[Drewminator]

hey everyone i have a question.my wrangler runs at 210 degrees water temp. all the time ,even on cold days ..is this normal?i just was wondering and is there a way to make it run cooler,a different thermostat maybe?i just bought a 17foot bantam flyer travel trailer.its running at 210 still but i'm afraid of the long grades.thanks

I have a 06 Rubicon and it runs at 210 degrees, twenty four seven. There is absolutely nothing to worry about; it’s a Jeep engineering thing.

Drew-

[blkTJ]

my TJ runs at 210 every time I drive it, since 1997. Towing or not.

[Black & Tan TJ]

I'll fifth that 210. Recently my thermo was stuck open and it still ran 210 until the outside weather got cold, then it ran maybe 130 - 150, then the check engine light came on. What happened was the engine/computer ran in "cold enrichment" mode until it couldn't correct the mixture for the O2 sensor.... check engine light. 210 or even slightly over is normal and OK.

B&T TJ

[Bachman]

Jeep engines have always run warm, even back in the AMC days. 210 is just were they want to live.

[wildbill]

Jeep engines have always run warm, even back in the AMC days. 210 is just were they want to live.

thanks everyone for your input!! i feel better about it now.guess its a jeep thing i'll never understand.as long as you fellow 4.0 jeepers say its alright i'm satisfied..thanks , bill

[Drewminator]

thanks everyone for your input!! i feel better about it now.guess its a jeep thing i'll never understand.as long as you fellow 4.0 jeepers say its alright i'm satisfied..thanks , bill

You’re very welcome!

Drew-

[Davisrats]

in the 1980s a lot of cars went to gauges without numbers so people would not worry about the temp as long as it was in the GREEN area. As fuel injection/engine managment has evolved the engine temperature has gone up.

[rgathright]

Technically speaking... the 210F makes the exhaust gas hotter. In turn the catalytic convertor, which is more efficient as the heat increases, can convert the exhaust easier. As a result... the 4.0L I6 can pass exhaust emissions testing that meets government standards.

Unfortunately this is also the reason the I6 was phased out in 2007 model years. The engine just couldn't meet the new federal regulations.

[wildbill]

thanks,i think i will invest in a tranny cooler since its an auto.or maybe even a tranny temp guage.its too bad the 4.0 had to go bye bye .its almost bulletproof..

[rgathright]

Excellent choice! Tranny temp guage first though, this will get you some experience with the system. Next when you install the cooler, use large AN size hoses that are steel braided. Why? Because those itself turns into a tranny cooler!

I did this with every 700R4, I found. Made a big difference because the flow rate was higher as well.