Bully Posi Traction differential for use in 1964-1972 Buick, Chevrolet and Pontiac Cars with GM 12-bolt rear differential provides smooth limited-slip operation and aggressive traction on a wide variety of terrains. This Posi unit is manufactured using a high-strength nodular case, forged 4320 chromoly spider gears and Raybestos composite clutches for strength, durability and long life. Whether you're at the race track or enjoying a ride on the street you will experience incomparable positraction performance.

Technical Note: Bully Driveline recommends the use of high-grade Non-Synthetic GL-5 gear oil and LSD (Limited-Slip Differential) additive for smooth operation and long life. The use of Synthetic oil is not recommended and may result in noisy or aggressive operation.