Eaton says the supercharger oil is good for the life of the unit. Slip the belt off of the supercharger and see if the pulley has play. If it does, pick up the coupler off of zzp website or wbodystore. The coupler is 25 and the charger takes 2-3 bottles of Gm supercharger oil. Use only the Gm supercharger oil. No other oil should be used.