I have a 2002 ram 1500 2wd 4.7 quad cab. It has 121k on it. It used to operate at normal temp ( just below the halfway mark). Recently, it started climbing, and now operates at exactly midway. When idling, it would constantly rise until I shut it off to cool off. Red light never came on. I didn't let it get that high. Now, if I'm going over 70mpg, the temp continues to rise. I have a new fan clutch, water pump, and thermostat. The heater core is bypassed. If I travel at 45-60 mph, the temp is pretty normal. But when I go over 70 it just raises up. Any ideas?

 

restricted radiator? I just had same type of issue. I ran mine to hot and cracked both heads. Learned I am losing water at the timing chain cover.

 

Could be the culprit. I'll replace it this weekend. Ill let you know what happens.

 

I 2nd the radiator restriction. VERY common 4.7L issue.
I'd do a flush before installing the new radiator so you dont gunk it all up. You should replace the t-stat while the system is open.

 

I will flush it beforehand. I will install a new thermostat as well. Thanks for the advice!

 

Be sure to come back and let us know what you find out