We sell reman differentials and final drives for replacement by our customers.  When failures are light and caught early this is the most cost effective way to repair these components.  This is especially true in the newer machines that use duo-cone seals to seperate the oil cooled finals from the differential section of the axle.  When you have catastrophic axle failure and contamination the best approach is to purchase an entire axle assembly with a reman differential, finals, and wet brake assemblies. Don't overlook your cooler! A stacked cooler cannot be reused after heavy failure. If you have any questions or concerns please call!