The other day when hauling with my 95 the water temp gauge got up to 220 and would not go down. This was the driving condition. 65 mph, 2200 rpm ,95 degree outside temp, driving with a good tail wind ,12000 pound trailer weight , semi flat road, 80 mile trip. I checked all the obvious, new air and fuel filter, fan clutch did engage and stayed engaged , radiator- condenser was clean and egts stayed around 900. Now when driving unloaded the temp gauge fluctuates from 190 to 160 like its supposed to. And in winter months the truck never attempted to run over 190 with even a 17000lb trailer load. This truck tows constantly and has never had this issue till the other day. Is 220 degrees normal in those conditions or do I have problems elsewhere? Thanks and any input would be greatly appreciated.

 

220* is not too hot, sounds like that "tail wind" was getting you. It helps with the load but kills the airflow through the coolers.
Keep an eye on it and if it happens again without the tail wind check your thermostat it may be getting sticky.

 

how many miles on raidiator, most cummins radiators start to plug up in side arownd 200k and do exactley what you are having trouble with.

 

220* isn't that bad once in a while... If it ran at that temp all the time then something may be wrong

 

I appreciate everyone taking the time to help me out. The truck has 118,000 original miles. Yesterday I had the truck in the barn and replaced the thermostat and blew the radiator and condenser out. Wasn't restricted at all. I went on a 100 mile trip, all highway at 65mph with gooseneck unloaded and did the same thing. Empty trailer weight is 6600lbs. The only thing I can think of is restricted coolant flow. Considering the age of the truck could it possibly be the radiator? I hauled a lot last year in this heat and never had a problem. The only thing I have changed to the truck is removed the auto and replaced with 5 spd. It's strange bc today it was 107 outside and I drove it 200 miles with no trailer and the thermostat operated correctly and cycled from 160 to 190