so i was wondering does putting a 165 degree thermostat in your truck when its suppose to be 185 have any effect on you're heat?

 

Yes. You basically wont have any. I like to use a 195 in the winter and a 185 in the summer.

 

Also not enough heat in an engine can hurt performance.

 

well think of it this way. The thermostat holds coolant back until it reaches a certain temperature i.e. 185f. when that's hit then it allows coolant to flow to the radiator. the largest reason why many oem applications call for the 185 degree thermostat is one, engine performance as said above. second, so that there is a good transfer of heat through the block and in the winter the heater core. What exactly made you wanna run with a lower thermostat?

 

With 165 you will have excessive cylinder and ring wear. I would run 195

 

When i first got my truck it had a 165 in it... not really sure why. The cooler thermostat helps performance a little, but really increases wear on the internals, increases emissions and virtually kills the heater. 180 or 195 would be the way to go. Some engines you can get a 210.

The only good thing about a 165 thermostat is that is the temp that makes an automatic the happiest.

 

Exactly! i'd run a 195 t-stat as well, or if you insist, certainly no cooler than 180.

HOTRODSRJ’s COOLING TIPS Operating temperature vs power and longevity!