Hi, hope I can get some help here. B250 [318] overheats within a few miles of driving.

to date I've replaced the Radiator, 'stat' [twice], water pump, checked the belt to make sure it's on in the right direction. although I don't think it will go on the other way. the truck will hold tempature OK while idiling?
Any Sugestions??

 

You either have a restricted cooling passage or you're installing your t-stat upside down.