I do not think that Ferrari ever really understood the forces involved in the rear axle of their cars. I am not claiming to be an engineering expert, but we have to repair major damage to about 2 to 3 Ferrari axles per year. Not only do they need new bearings and seals, but they also commonly suffer from broken bearings or damaged ring and pinions.

Other make’s axles seem to go bad because of high mileage or being run without grease. Ferrari axles self destruct because as you can see from the photos, the bearings used are to allow the pinion only to spin and do not account for the incredible axial thrust put upon it when power is applied or the car is coasting against the engine.

If the ring and pinion were straight-cut gears this would not be a problem. Yet with spiral cut gears, the fore/aft load is huge and Ferrari only used roller bearings on the pinion.

On the differential carrier, they used large single row ball bearings, which again, offer little in handling the side loads.

I never replace the bearings with the original type and set these axles up with tapered roller bearings on the pinion and diff carrier. I have done this to many cars over the years and have had none of them fail. This Lusso axle is next in line, followed buy a 212 axle, and then a 166 axle.