OK....I have a 2000 5.9 and was wondering if I can use the 160 thermostat and still be safe? Problem...The heater doesnt heat up! The temp gauge isnt going up above 170. Not sure if the thermostat that i have in it now is opening as it should. Not smelling antifreeze inside the durango so not thinking its the heater core. Running out of options as I have 3 kids that are freezing every day due to lack of heat!

 

160 is too cold, 180 is ok, and 195 is stock

if the truck is not warming up properly i would expect a stuck open thermostat myself

 

Thank you! Bad thing is, I have replaced the thermostat twice. It had a 195 in it to begin with and dropped it to a 180 and still having the same problem.

 

when you get the new thermostat put it in some water and bring it to a boil, this will allow you to confirm that it is opening at the correct temperature.

also make sur eyou have enough coolant in the system and that your fan clutch is NOT locked up.

 

Thanks! I will do that!

 

The worst is when the thermo gets replaced and i doesnt open and you get stuck wondering what happened now. Confirming it works before it goes in is always a great idea. And i agree with shrp check coolant level and maybe even test the coolant with one of those cheap pump testers.

 

Make sure you've bled/burped the system of air pockets too.

 

Anthony Kurt,

BTW, lowering the temp of the thermostat would lower the heat available to the cabin. To get higher heat through the heater core go back to the stock 195 thermostat.