DIFFERENTIAL FRICTION MODIFIER & BREAK-IN ADDITIVE- is a friction modifier designed to reduce limited-slip noise and to aid the proper break-in of any differential. This can be added to any gear oil to reduce temperature during break-in and prevent gear softening. Replaces manufacturers' limited-slip additives. Can be used to perfectly tune a limited-slip unit. Red Line 75W90 and 80W140 Gear Oils already contain this additive.
