Red Line Limited Slip Friction Modifier Compatible with both petroleum and synthetic gear oils  Reduces break-in temps as much as 50F  Add 1oz at a time to clutch-type limited slip or posi-traction units to eliminate chatter Recommended Dosage: Use 4% for prevention of limited slip chatter in broken-in units (typical one 4 oz. bottle) or 4 to 8% for the break-in of new differentials. Red Line Limited-Slip Differential Friction-Modifier / Break-In Additive will significantly reduce the friction during break-in of differentials. High temperatures encountered in break-in can destroy the hardening of the gear teeth causing rapid wear of the softened gears. This additive can reduce the break-in temperatures by as much as 50°F, improving break-in conditions. Compatible with petroleum or synthetic gear oils. Red Line Gear Oils already contain this additive (except the NS). In non-limited-slip racing differentials and quick-change units using the Red Line ShockProof Gear Oils an additional 3 to 6% Red Line Limited-Slip Differential Friction-Modifier / Break-In Additive is recommended.