Hey Guys - not sure if this has been asked before but always good to have a current discussion. In the summer I installed the 180° thermostat. Now the weather is starting to get colder and I have been observing the behaviour of the temperature gauge on my dash. In both summer and winter, at operating temperature and while idling, my temp gauge sits a little shy of half way. But recently I have been watching the gauge drop right down to the 'C' when I accelerate (moderately aggressively). I do allow a little bit of tolerance between the thermostat status as well as the coolant temperature sensor, but I am wondering if seeing the needle drop all the way down is of any concern?

Fia has a front winter cover that would work for my truck, is anyone running something like this to offset the lower thermo temp? Are people running 195° in winter and 180° in summer? Do my findings suggest and inaccurate coolant temp sensor?


P.S. On the hypertech tuner you can select 180° or 195° for the thermostat in vehicle. What does changing this do? I expected to see an adjustment to the scaling of the temp needle, but don't want to jump to conclusion.

 

Just wondering why you are running a cooler t-stat? Had been told years ago it was a bad idea, but never really looked into it that hard.

 

If you don't have other mods, that are expecting a 180 stat, (like, for instance, a tuner.....) then no, it doesn't do you any good, and can actually make fuel mileage worse.

 

I live and drive around in a fairly cold climate in winter. Canadian prairies.

The engine temperature gauge runs steady at normal thermostat temperature, regardless if it is 85deg summer day or -20deg winter drive to the curling rink.

If the temp goes up and down as you describe, the problem is not the set temp of the stat (180vs195) or a open/close winter front. The problem simply put is the stat has failed. They fail open, and that shows as no temperature control with the temp gauge going up and down on windspeed and rpm.

Please replace the failed thermostat.

 

I came here to followup and I see FaceDeAce has hit the nail right on the head. I drained cooling system and removed thermostat. As described above, I discovered the thermostat had failed open. It was replaced with a 195 Mopar from the dealership and all issues related to engine temperature have been resolved.

Probably just going to stick with the 195 moving forward.

Thanks all!