I have a 48 3/4 ton with a 1960 235 in it.Its been on the road for 2 years now and all of a sudden in the past week everytime i drive it at highway speeds it pours antifreeze out the overflow tube when i shut it off.It has a waterpump from Carter and a new 160 T-stat.It never overheats and only started this problem in the 90 degree days we are having now.Any suggestions?
