so ive noticed im have an issue with the water temp guage. before it was like the thermostat was sticking shut for a bit, it would hit about 200 degrees then settle down to 190 where it belongs. then this morning i noticed it was at about 160, after pulling a long hill where it usualy reaches normal 190 temp. it then went down and settled at about 150. it never went any higher than that the rest of the day. im guessing its a bad thermostat. oh ya, and the heater didnt blow quite as hot as normal. so im guessin that, but i didnt know if anyone had any advice. thanks guys.

 

Your thermostat is probably suck open now. I had the same issues before I changed mine. I could drive to work, about 25 minutes on the hiway, and barely reach operating temperature. My therm would stay open, preventing heat from being made. After changing it, everything worked properly.

Here is a link to a how to video if you need it.

https://www.dieselbombers.com/24-val...winterize.html

 

mine does the same thing goes to 200 then back to 190 i bought a new thermostat for mine today im gonna put it on sunday if all goes well i will tell you if itfixs it urs definitly sounds like the thermostat and its only 30 bucks to fix hope this helped.

 

I would get the thermostat from Cummins....dont use a cheap parts store one.

 

thanks guys, that really helped, the video answered any questions. i thought it was gonna be a bigger pain, ive changed the coolant but not the t stat. ill make sure to order one from cummins. thanks again