I have a 2004 2500HD 5.7 and it has been running hot. I changed the thermostat and it is still running at 3/4 on the dashboard gauge. I do have heat and cannot smell anything from the engine. The temp of the air blowing from the heater does go up when driving and down when I stop.

Any thoughts

 

Moving this to 3rd gen Ram, you'll get more answers here.

 

Air in the system, maybe? Park it nose up and run with the cap off and heater on 'til it reaches operating temperature. That may burp out any air trapped in the passages.

 

Oh, and Welcome to DF!

 

did you test the t-stat before you put it in?
if burping the air a few times doesn't work, radiator may be clogged. I think the pumps okay if it stays steady at a temperature. Could be the clutch fan too, maybe its only coming on at the higher temp now?

 

Normally when i see this i think low coolant level