i have a 98 dodge 2500 4x4 360 . i changed the thermostat 3 times now , and 2 new radiator caps . and temp sending unit . and im running to cool . temp is about 160 . heater is not hot . yes i've burped and flushed everything . put cardboard in front of radiator , blocking the whole thing and still at 160 . whats the problem ? ,

 

are u sure the temp gauge is correct

 

it was with the old tstat . then the first replacement showed about 160 [ failsafe ] so i figured bad stat . got it replaced with same [192*] went to 200 for a minute then went down again . replaced sending unit and sat [ oem replacment ] 195* still the same up maybe 10* radiator and upper hose , are warm . temp goes up when you shut the engine off for a few mins the drops fast.