Pontiac Oldsmobile buick camaro chevy 8.5. 1971 1972 1973 1974 1975 1976 1977 with 8.5 rear end. ANY OTHER 8.5 with 28 spline. Check the numbers to be sure. 2.56 POSI rear are not the best ratio. Pinion has the correct tooth count.   Will or SHOULD need bearings replaced. Payment in 5 days plus  shipping and handling to the lower 48.