1989 Gmc Truck 89 Chevy That Keeps Over Heating Coolant Dissapearing New

Have you checked to see if there is coolant mixing with the oil and the opposite?

Much more common on the GM V-8 engines is a leaking intake manifold gasket.

The oil has no coolant in it i alrdy checked that. Im pretty sure its the intake gasket. But i dont wanna tear into it and have it be somthing else. I fill the system with coolant a nd it all disappears. It isnt leaking on the ground.

And is there any way to test to see if the gasket is bad?

Pressure test may show it, but you can also add a small bottle of dark purple dye. The coolant may be evaporating as fast as it leaks out. After a few days, search with a black light. The dye will show up as a bright yellow stain that you can follow back to the source.

Okay well thanks. But am i right is it a head gasket? Cause thats what everyones telling me. Thats the only thing i can think of. Cus it doesnt leak on the ground cus u dnt see it in the snow. And plus some eater comes out of the exhaust when it is running

Sure it could be a leaking head gasket but that would be a lot less common. You may be able to verify that with a chemical test at the radiator. With the engine running, air is drawn through a glass cylinder with two chambers partially-filled with a special dark blue liquid. If combustion gases are present that liquid will turn bright yellow.

If you think coolant is going out the tail pipe, the dye will show up there too.

Okay thank you for your help ill let you know what happens with it