Precision 99193 Transfer Case, Crankshaft and Differential Pinion Repair Sleeve Repair Sleeves are used when a groove has been worn into the shafts sealing surface The sleeve is used with the existing seal and comes with an installation tool Item is a precision engineered sleeve made from Stainless Steel to extend the life of the shaft Our repair sleeve restores your worn yokes and shafts to give them new life Repair Sleeve provides lower coefficient of friction