180 Thermostat

CapnDean · April 17, 2001

To the experts:

My 2001 GMC SLE temp reads just above 200 degrees when the truck reaches operating temp. It gets even higher when I tow a small trailer or get it up on the highway at high speed. I realize that the truck is not overheating, and I understand that GM has installed a 195 T-stat for a reason. What benefits/detriments am I likely to see by dropping the stat to a 180?

I have always understood that 180 is optimum temp for gasoline/diesel engines.

anybody got any thought on this?

gmcblu · April 17, 2001

*Without going over the boiling point* for the coolant, the hotter an engine runs the more efficiently it runs. Changing to a cooler thermostat will allow it to start cooling sooner, but won't keep it from overheating (which you said is not a problem).

BTW, these factory gauges are not very accurate and I don't give them much credit. There's another topic in this forum entitled "Fluctuating Temp Gauge" that addresses this.

Roofer · April 17, 2001

I have a 180 Hypertech Powerstat. When I first installed it, it ran about 200-210 like a normal T-stat was in. Now since winter, it runs right at about 180. Pretty wierd if you ask me.

CapnDean · April 18, 2001

Roofer:

Did you notice any changes in performance after you replaced your t-stat with the 180? Did you set off any codes, lose mileage, performance loss/gain or anything?

I would personally feel more comfortable having a little more cushion between operating temperature and boiling over. I realize it's probably a non-issue (heck if it never boils over who cares!) But with years of experience with Detroit Diesels and a multitude of Bowtie V-8's .... I just like seeing 180 on the temp gauge!

Roofer · April 18, 2001

Seemed to run a little stronger since I installed it. Hard to tell the little differences till they are gone. It goes well with my Hypertech Programmer. I have no idea on mileage, cuz I never really check that often. Hope this helps.