Welcome to the Air Forums Dane.
You will have to contact Freightliner with your chassis # to see if the larger rad is available for that chassis. Yours should be a XC chassis but they will want the F/L # for parts.
Have you determined that the temp. reading is accurate? Have you got a good rad cap on there giving the proper pressure? Overflow tank is working properly and coolant proper level and DCA content correct, etc? These engines require quality products for long life.
Is this the alarm or just the gauge reading that is showing hot? The alarm on these are a historical problem.
I suggest you first talk to a qualified Cat facility which, probably your closest, would be Casper or Gillette "Wyoming machinery Co" .
I have no direct knowledge of Cat engines other than the older 3406 model from the 80s so your best bet is a professional shop if you have an ongoing problem.
Originally Posted by mcintosh1969
I have changed the thermostats, tightened the water pump belt, new fan blade, steam cleaned the air to air and the radiator and rerouted crankcase breather tube. On recent trip temperature runs normal until we started climbing (towing a 18' trailer with 2 motorcycles) and the temperature started climbing. Does Airstream or Freightliner offer a bigger radiator for this unit?