Novak Conversions Jeep Wrangler JK shifters

Antifreeze temp rarely gets over 175

Largehit71

JK Enthusiast
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Jackson MO
So is a 180 degree thermostat stock on a 08 Jk? Never really noticed until I was checking with a OBD phone app. I’m thinking if it was not supposed to be there the ECM would let me know. Just seems like a low coolant temp.
 
My 08 runs hotter than that, it's still on it's stock T-Stat.

When it gets close to 180 the thermostat opens up until the temp hits 170 then will close . So I know it’s a 180 thermostat just wondering if a previous owner put a lower temp one in.
It’s ran fine for 4 years so ….
 
When it gets close to 180 the thermostat opens up until the temp hits 170 then will close . So I know it’s a 180 thermostat just wondering if a previous owner put a lower temp one in.
It’s ran fine for 4 years so ….

I would think if your not getting a CEL for low temperature your ok, that is if it does do a low temp CEL.
 
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Stock thermostat for the 3.8L engine opens at 210. Changing to a 180 is fine, and running the engine cooler can be a good thing. To really make a difference, the fans also need to be programmed to come on at 180. Even lower thermostats are available; I run a 165 in the Vette.
The ECM expects the Jeep reach operating temp (normally 210) within a short time (I think it's about 10 minutes or so) after starting. If it does not, it will throw a "thermostat rationality" warning and your CEL will come on.
 
The OEM t-stat on the 3.6 is set at 203. Don't ask why, I don't know. When my t-stat stuck open a few years back, the CEL came on and JScan told me "engine not operating at proper temp." It's was still getting up to 180+, and it had no effect on the engine, but waiting on heat and defrost was a pain in the ass.

Side note- had my tires rotated last week after I had just finished checking all the fluids, and the guy at the shop filled the coolant reservoir to the cap. Needless to say, when I got home the engine smelled like I just blew the head gasket....

Just a reminder, the reservoir has 2 lines on it that show you where the coolant level should be when the engine is cold or hot. And neither of those lines is near the top of the reservoir.
 
The OEM t-stat on the 3.6 is set at 203. Don't ask why, I don't know. When my t-stat stuck open a few years back, the CEL came on and JScan told me "engine not operating at proper temp." It's was still getting up to 180+, and it had no effect on the engine, but waiting on heat and defrost was a pain in the ass.

Side note- had my tires rotated last week after I had just finished checking all the fluids, and the guy at the shop filled the coolant reservoir to the cap. Needless to say, when I got home the engine smelled like I just blew the head gasket....

Just a reminder, the reservoir has 2 lines on it that show you where the coolant level should be when the engine is cold or hot. And neither of those lines is near the top of the reservoir.

Whenever I had my Jeep in I specifically tell them not to touch fluids .
Cause yeah , there are many people out there who mean well . Their Just clueless .
 
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Whenever I had my Jeep in I specifically tell them not to touch fluids .
Cause yeah , there are many people out there who mean well . Their Just clueless .

Yeah, I had some experiences...

Ended up costing me $300 to have the coolant flushed because some idiot topped off the Jeep's coolant bottle with washer fluid. Brain dead morons work in oil change places.

Then again, I had the Ford dealer do the oil change on my old Focus while on my lunch hour from the powersports dealership. Drove it back to our shop and walked out at quitting time to find all the oil on the ground. Dipwad rookie tech forgot to tighten the drain plug. They towed it back and had a "better" tech fix it.
 
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Whenever I had my Jeep in I specifically tell them not to touch fluids .
Cause yeah , there are many people out there who mean well . Their Just clueless .

My fault. I didn't think that asking for a tire rotation would necessitate anyone even lifting the hood. They've not done it before and the shop owner is a vet and a Jeep gy.
 
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Novak Conversions Jeep Wrangler JK shifters