Do not mix! There may be viscosity differences, additives, tagents and detergents that are not compatable. The complexity of lubricants and oils has really changed over the years along with the bases they are made from.
86 Pontiac 2+2 69 Firebird Coupe(Under Construction) 69 Firebird 4 speed Vert Driveable but Under Construction 64 1/2 Mustang (Under Construction) 86 Z28 Convertible Weekend driver
