Where is the temp sender located? It seems like it takes quite awhile for my temp gauge to move but the block feels warm as do the hoses going to the radiator. I can feel the left side of the radiator warming up first but the right side was still cool to the touch after 5 miles of driving as was the water when I took the cap off. Just wondering if the thermostat is hanging up? Is the thermostat located under the elbow on top of the cylinder head from the top radiator hose? If I do have to replace the thermostat, which is the one to buy?

 

That is correct location of Tstat and coolant sensor is very close by.
Most everyone finds the Dodge / Cummins OE tstat works best. However there are those preaching success with NAPA. Diesel are not the fastest at warming, and when very cold many put a cover in front.

 

5 miles doesn't even move my guage. They are cold blooded beasts. If you aren't experiencing other signs of a stuck thermostat, you are probably ok. Mine hovers around 190 when warmed up. it only goes up a little in the summer.

Kurt

 

Temp sensor is located just below the T-Stat.
190* is stock. Recommend Cummins parts only but your choice.
I run 180* in summer. Much more stable and does not overheat coolant as quickly when towing or racing.
Works great in TX. Should work well in AZ summers.
Cummins 190* - PN 3946849
Cummins 180* - PN 3967195

RJ

 

Concur 100% with RowJ. Switched to a 180-degree a few wks ago--works great in Tx; should work even better in AZ (AZ's just too HOT for me). Also SUPER-EASY to change; 3screws on the elbow and all are EASY to access.

 

If ya decide to replace it this`ll prolly help:

http://www.dodgeram.org/tech/dsl/coo...thermostat.htm

 

BE easy on the draincock. Its plastic and can strip out easily. Just a heads up!

Kurt