For 1978 GMC G15 Radiator Cap 42552PRZX Safety Lever -- Relief pressure 16 lb

For 1978 GMC G15 Radiator Cap 12398JZPM Standard -- Relief pressure 16 lb

For 1978 GMC C15 Radiator Cap 57133CV Safety Lever -- Relief pressure 16 lb

For 1978 GMC G15 Radiator Cap 88938GDGK Safety Lever -- Relief pressure 16 lb

For 1978 GMC G25 Radiator Cap 64828MCDH Standard -- Relief pressure 16 lb

For 1978 GMC K35 Radiator Cap 66131RJHC Standard -- Relief pressure 16 lb

For 1978 GMC G35 Radiator Cap 92352DTHH Standard -- Relief pressure 16 lb

For 1978 GMC K25 Radiator Cap 46941NRGD Standard -- Relief pressure 16 lb