I have a 96 ram 5.9. It overheats to 230 and sometimes higher. It bounces around from 200 to 230 once ive been driving a while. When my truck is running the coolant doesnt curculate itjusts sits there so i replaced the thermostate and its still doin it. Does anyone know what else it could be.

 

First feel around the radiator once the engine is hot. If only part of the radiator is hot, it's plugged up and needs to be flushed/rodded, or replaced. If the engine is hot and the entire radiator is cold, it's prob the pump. Do you get heat from the heater vent?

 

Moving to 2nd Gen section, bump to the top.

 

Check the thread in my sigline about running hot. Could be an air pocket or it could be a worn impeller on the water pump.