I have changed the intake gaskets and the head gaskets
Everytime I put antifreeze into the radiator the engine shakes and stalls out . on 1998 Buick Park Avenue
Have you pressure tested the cooling system BEFORE trying to start it , to find out where the coolant is going? globalhelper is more than likely correct.....otherwise try green jelly radiator sealant and top-end salve.........
DID YOU HAVE HEADS CK'D FOR CRACKS IF SO YOU MAY HAVE DAMAGED A GASKET WHILE ASSM UPPER HALF OF ENG