Help support the pinion shaft as it turns under load with the National Differential Pinion Race / Manual Transmission Pinion Race, part number HM89410. It is a direct-fit replacement for many vehicles, among them the 1964-1973 Ford Mustang, 2000-2009 BMW X5 and 1974-1994 Alfa Romeo Spider, with fitment cataloged for all engines. See the Buyer's Guide tab for the full list of applications.
A pinion race is the outer ring of a pinion bearing. It sits in the housing bore and gives the bearing's rolling elements a surface to ride on as the pinion shaft turns. HM89410 is listed under both the differential pinion race and manual transmission pinion race names.
- Dual listing: Cataloged as both a differential pinion race and a manual transmission pinion race.
- Position: Cataloged for front outer, front inner, rear outer, rear inner and outer positions, depending on the application.
- Quantity: The listed applications use one per application.
- Coverage: A wide range of Alfa Romeo, Aston Martin, BMW, Chevrolet, Ford, Plymouth and other models.
Signs this part may need replacing include a whine, howl or growl from the differential or transmission that changes with speed or load, excess pinion play, or a race surface that shows pitting or spalling on inspection. Noise can have other causes, so diagnose before replacing. A race and its bearing cone wear together and are commonly replaced as a set; consult the vehicle service information for installation and pinion setup procedures.
