Union 76 gear oil is a conventional non-synthetic 80W90 formulation designed for all types of differentials. This kit includes three quarts of oil and a bottle of Yukon Limited Slip Friction modifier that reduces noise and chatter in clutch driven positraction units and limited slip differentials. 3 quarts of Phillips 76 80W90 conventional gear oil with bottle of Posi additive (limited slip friction modifier). 3 Qt. 80W90 CONVENTIONAL GEAR OIL W/ POSI ADDITIVE, GL-5