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I have been doing a little research but can't seem to find what I'm looking for. Does anyone know if there is a 180 Degree Thermostat that is compatible with the SXT V6? I believe the stock is 195-200 degree.
 

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I will second @A Guy’s assertion about running a 180F thermostat in a 3.6L - it is unlikely to provide any beneficial results to the average daily driven 3.6L Challenger.

There are some who even say that particular mod on this particular engine can result in a loss of performance and reduction in operational efficiency of several engine components. I am one of those people, though I believe the negative results are relatively minor and likely not noticeable to the average driver.

However that doesn’t mean the cumulative effects of the negative results couldn’t be noticed once enough time and miles have been logged with the 180F thermostat in a 3.6L.

Bottom line: unless you are addressing a specific need that requires a lower temp thermostat (and can adjust the PCM’s various fan settings accordingly), you should run the stock temp thermostat in a stock (or even lightly modified) 3.6L.
 

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I believe the manufacturer has reasons for choosing what temperature an engine maintains stock. Sometimes retaining heat is advantageous, and various efficiencies may depend on it. If it were for gas mileage only, and changing it resulted in great power increases, and power was your primary concern, then yes, by all means. But I doubt that is the case. I do think the temps it runs stock have to do with fuel economy as well, but these 3.6L engines are pretty much optimized. Not saying a tune and a 180° thermostat will not net you some HP, almost certainly will, but more than a tune alone?

A Guy
 

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Agree with those above. I wouldn't mess with the thermostat in these cars. Manufacturers spend a fortune and a ton of time to determine the best thermostat temperature to use for their engines.
 

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The stock thermostat temperature of 203F that Dodge uses is in line with all other automotive manufacturers’ stock thermostat temps for the engines in vehicles sold in the US. At first glance that might seem very odd that every manufacturer came to the same conclusion when deciding what temp to have their engines’ thermostats open up, given they never agree on anything else with regards to how their engines should operate.

The fact is it’s no coincidence. That temperature, or 100C to be more precise, is the temperature at which modern engine oils are certified to deliver the advertised specs. That’s the temp they get tested at, and that’s the temp at which they will do what the oil company promises they will do - maintain certain viscosity with advertised shear rates, etc.

To operate an engine at a temperature other than the 100C means inefficient behavior from the engine oil and then from the engine itself as a result. Is the difference significant? No, not in an immediately noticeable sense. But less than ideal behavior from the engine oil, and the resulting inefficiencies of the engine itself, will eventually add up to noticeable results over time.

Maybe that takes so long the original owner will have gotten rid of it by then. Maybe not...

Food for thought.

Mmmmm...food...Nuke hungry...Nuke go find food now.
 

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There was a tuner on HP tuners forum that said if you want more power go with a 180F thermostat but I fail to see how it helps with power especially on these modern engines. I used to think a lower thermostat helped with heat soak but it does not. I run a 195F thermostat and adjusted the fan temps accordingly and during stop and go the ECT is similar to stock. It is only on the highway that I see ECTs around 195-198F as opposed to 203-206F but it has little effect on IATs. These engines go into closed loop (stock tune allows CL when ECT is as low as 50F) within several seconds after you start them and when in CL the PCM tries to maintain an AFR of 14.5...so how does a cooler thermostat add power? The downside of a cooler thermostat is if you live in the northern part of the states and run a 180 thermostat there is a good chance you will get a P0128 code (engine not at proper temp).
 

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I have looked into running a 180F thermostat since acquiring the Hemi, but I too remain unconvinced the benefits outweigh the drawbacks. A significant negative that occurred to me, and which I never see addressed, is the introduction of yet one more variable to the diagnosis equation when something is amiss with engine operation/efficiency.

<typical thread on LX themed forum>

“My Hemi MPG suuux!”
Or
“My Hemi just doesn’t run right anymore!”
Or
“Plz help, URGENT!! Why is my Hemi throwing all these strange codes??”

Is always followed by the same old replies

“Blah, blah, blah, spark plugs, CAI, heat soak...”

None of that helped? Dang, IDK, sorry man, take it to the dealership.

Oh wait, I see you are running a 180F thermostat. Ouch, your day just got longer. Replace that with a stock temp one and restore stock fan settings, and then REDO all the troubleshooting steps!

<rant>
You cannot try to diagnose nebulous problems on these cars without utilizing precise data and approved procedures if you hope to have any success. Leaving important criteria like engine coolant temp out of the equation throws the whole equation off! Results cannot be trusted and have to be verified in every scenario if you leave things to chance like that!
</rant>

And that’s all I have to say on that matter! (Unless I think of something else, then I reserve the right to go on another rant!)
 

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Tons on conjecture and assumptions here. As someone who monitors temps closely and runs a 180 tstat in the summer, I can tell you confidently that my oil temperature is almost exactly the same regardless of the thermostat. The oil squirters on the SRT engines ensure a high oil temp, I can't speak with such certainty about the 3.6 or 5.7 but you guys are also missing another big point, the main reason all auto manufacturers run 200 degree thermostats is for emissions purposes.
 

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There were papers showing higher ECTs reduce certain emissions but also increase MPG.

I recently read this article where it states a lower thermostat can help reduce dramatic temperature fluctuations within the cooling system. Basically at lower engine loads the radiator will expel more heat from the coolant so when the engine experiences high loads the cooling system is ready to absorb the additional heat, thereby reducing/eliminating the chance of overheating.

http://www.superstreetonline.com/how-to/aftermarket-parts/1308-low-temp-thermostats/

But I still wonder how much benefit there is to a lower 180F temp as the engineers probably designed the system to run at optimum temp already? :dunno:

Only reason I went to a 195F thermostat is because I went FI and that added power generates more heat during WOT. I also installed an all aluminum radiator which I read does not really perform that much better than the stock radiator...but I won't have to worry about the seal between the plastic tanks and aluminum core.
 
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