6.5 chevy turbo diesel, how can you tell if the head gasket is gone? There is no coolant going into the oil, there is up and down heat in the cab. I changed thermstat and no different. Lots of pressure in top rad hose and it releases when I loosen the read cap.

 

welcome to db! with the radiator cap off, crank up the truck and look in the radiator. usually if the head gasket is blown, you will see the coolant bubble up.

 

You got a leaking head gasket. Chances are good, it's on the passenger side. But, I'd do them both at the same time.

 

Please update.

 

Updates??

 

Closing from lack of updates and only 1 post.