1990 GMC P4500 4.3L V6 GAS. 1980-1989 GMC P4500 4.8L 6 Cyl GAS. Notes: Radiator Cap/Cooling System Tester Adapter -- System adapter on tester. Ensure Proper FitTo confirm that this part fits your vehicle, enter your vehicle's Year, Make, Model, Trim and Engine in the Compatibility Table.
