Ideal temperature for the 4.0?

ivarr

ivarr

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the inline 6 cylinder 4.0 liter is the only engine i'm referring to in this thread.

i'm on my second jeep. 1st was a 1994 cherokee country ( " the baby cherokee " ). bought it with 145k miles drove it to 224k. always ran a 195 degree thermostat, never any problems.
2nd, now, a 2006 wrangler sport / tj. bought with 68.5k now at 128k. put in 2 thermostats since i've had it, both were 195 degree.

3 weeks ago had an appointment to have the ac compressor, condenser belt and belt tensioner replaced then 4 or 5 days before that happened i blew the radiator after driving for about 2 miles and was doing maybe 35mph when it happened. pulled over in about 125 feet and it got towed to the garage.
so got them a radiator and they did the thermostat as well.
had an issue with a thermostat code over the next week so they said sensor and changed it. no more code throwing
now temp gauge says 210. it's constant but does seem hot when i open the hood and might be hearing a little pinging from a heat shield or something when i get out, but not sure i'm right about that.

is 210 too hot ???
should i just go back to a 195 thermostat ???
 
I tried to run a little cooler thermostat in my 06 but it would take to long to heat up and would throw a code. Gonna install a Hemi and run the temp where I want it:)
 
So I've only had my TJ for a few weeks and only driven it a handful of times, but I noticed recently, that first thing in the morning when engine is over night cooled, the temp gauges shoots right up to 210 on the gauge within 2-3 mins of driving and pegs 210 for the rest of the day. I've never seen a temp get to operating temp that quickly. Is this normal??
 
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The Flying Scot said:
Is this normal??
Click to expand...

Fairly.

I'd do two things...one, use an ODB reader to verify the PCM's reported temperature. A $30 Bluetooth dongle and the free Torque Lite app will do this.

Second... verify the PCM's reported temperature with an IR thermometer on the thermostat housing. Also less than $30.

-Mac
 
lowell66dart said:
I tried to run a little cooler thermostat in my 06 but it would take to long to heat up and would throw a code. Gonna install a Hemi and run the temp where I want it:)
Click to expand...

So I understand, you chose NOT to use the 195 thermostat that the 4.0 was designed to have so that it would come to temp properly.

You chose to put a Thermostat that was lower, and as anyone would predict, the engine didn't come to temp fast enough due to having a lower thermostat.

Your comment is "I'm going to replace the engine with a Hemi, so that I can run what temp I want."

You're joking, right? That's the reason you're going to completely swamp in a different motor? Free country, just seemed like you're joking, but maybe you're not?
 
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There should not be any extra fuel added with a 180 degree thermostat. I run a 180 degree thermostat and runs 182 to 185 degrees according to the ALDL.

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ivarr said:
the inline 6 cylinder 4.0 liter is the only engine i'm referring to in this thread.

i'm on my second jeep. 1st was a 1994 cherokee country ( " the baby cherokee " ). bought it with 145k miles drove it to 224k. always ran a 195 degree thermostat, never any problems.
2nd, now, a 2006 wrangler sport / tj. bought with 68.5k now at 128k. put in 2 thermostats since i've had it, both were 195 degree.

3 weeks ago had an appointment to have the ac compressor, condenser belt and belt tensioner replaced then 4 or 5 days before that happened i blew the radiator after driving for about 2 miles and was doing maybe 35mph when it happened. pulled over in about 125 feet and it got towed to the garage.
so got them a radiator and they did the thermostat as well.
had an issue with a thermostat code over the next week so they said sensor and changed it. no more code throwing
now temp gauge says 210. it's constant but does seem hot when i open the hood and might be hearing a little pinging from a heat shield or something when i get out, but not sure i'm right about that.

is 210 too hot ???
should i just go back to a 195 thermostat ???
Click to expand...

Totally normal.
 
The Flying Scot said:
So I've only had my TJ for a few weeks and only driven it a handful of times, but I noticed recently, that first thing in the morning when engine is over night cooled, the temp gauges shoots right up to 210 on the gauge within 2-3 mins of driving and pegs 210 for the rest of the day. I've never seen a temp get to operating temp that quickly. Is this normal??
Click to expand...

Yes
 
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Winter or Summer , ours gets to 210 pretty quick and stays there . Rarely does it get over 210 . Idling with the air conditioner on in 100 degree weather it might hit 215 or 220 if sitting still for a long while , but in normal stop and go traffic it stays at 210 .
 
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cpwolf said:
So I understand, you chose NOT to use the 195 thermostat that the 4.0 was designed to have so that it would come to temp properly.

You chose to put a Thermostat that was lower, and as anyone would predict, the engine didn't come to temp fast enough due to having a lower thermostat.

Your comment is "I'm going to replace the engine with a Hemi, so that I can run what temp I want."

You're joking, right? That's the reason you're going to completely swamp in a different motor? Free country, just seemed like you're joking, but maybe you're not?
Click to expand...

The main reason I want to run a lower temp thermostat is to help with the tranny temp. Ten or fifteen degrees on that fluid temperature is a big deal to me. I have always ran 180 stats and never saw any issues until this Jeep with the CEL thing.. And a Hemi is in the works.
 
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lowell66dart said:
The main reason I want to run a lower temp thermostat is to help with the tranny temp.
Click to expand...

You could install an additional cooler...Derale makes some quality ones. Either in lieu of the one in the radiator or in addition too. Some folks have also installed deeper pans... although I don't recall the efficacy of that on TJ 32s and 42s.

-Mac
 
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macleanflood said:
You could install an additional cooler...Derale makes some quality ones. Either in lieu of the one in the radiator or in addition too. Some folks have also installed deeper pans... although I don't recall the efficacy of that on TJ 32s and 42s.

-Mac
Click to expand...

+1 on the trans cooler. My temps were routinely over 200 after the rebuild, but haven't been over 170 since adding a Hayden cooler in front of my radiator.
 
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The Flying Scot said:
Thanks. I'll look into getting that done.!
Click to expand...

Yeah, an auxiliary cooler and temperature sender and gauge will solve the tranny problems. There's no problem with the engine temps reading 210*. The 195* thermostats open at 195* and the temps creep up to 210*. Completely normal. Putting in a 180* thermostat won't provide any significant help to your transmission temps.

The Setrab 53-10748 is a great cooler that is mounted behind the grille in front of the radiator on the V bar.

https://www.amazon.com/dp/B07C64FTTK?tag=wranglerorg-20
 
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Just to pile on - our rig has electric fans behind the radiator, small hood vents and a fresh oem cooling system. 210° is where our gauge is pegged in cool weather or hot weather, idling, cruising at highway speeds and also when we went rockcrawling on an 8/10 trail for 2-3hrs of 4low, locked wheeling.
 
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210-220 is factory and best for efficiency and longevity.

I've noticed it makes power when it's a little cooler, but I still run the factory t-stat
 
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