I've had my 96 CTD for about 2 mo. now and have noticed that when at high way speeds the temp gauge swings from about 150 to 180 degrees, if I watch it I can see it move. It seems to cycle about every 20 to 30 seconds. I am new to the diesel world but I don't think this is right. Am I looking at a new thurmastat?

Thanks
Floyd

 

sounds normal, it is just the thermistat opening and closeing. as long as you dont go over the 220-240 for too long your good.

sometimes I wish my 24valve HPCR Cummins had the 12v chatter