TF-81SC Transmission 47-Tooth Differential Gear Housing

This is the differential gear housing, also called the differential case, for the Aisin TF-81SC six-speed transaxle. It carries 47 teeth on the final drive ring gear and holds the spider and side gears, the pinion shaft and the carrier bearing journals. It replaces OE reference 45822-24000 and fits units also badged TF-80SC, AF21 and AW6A-EL depending on the vehicle manufacturer.

Fitment covers 2006-2007 Ford Fusion 3.0L, 2007-2011 Lincoln MKZ 3.5L, Mazda 6, CX-7 and 2007-2011 CX-9 3.5L and 3.7L, and 2007-2011 Hyundai Veracruz 3.8L. Confirm the ring gear tooth count on the unit you have before ordering. The TF-81SC family was built in more than one final drive ratio and a 47-tooth housing will not mesh with a transfer gear cut for a different count, so count the teeth on the old housing rather than going by model year alone.

The differential on this transaxle sits in the same case as the gear train and shares the ATF, so when it goes it puts steel through the whole unit. The common failure is the pinion shaft galling in its bore and the side gear thrust faces wearing through, which shows up as a whine or a growl that changes with road speed instead of engine speed, a clunk on tight turns, and glitter in the pan. Once the housing bore is worn oversize you cannot shim your way out of it - the housing is the part that has to be replaced.

On the bench: split the case, lift the differential out with the transfer gear still stacked, press off the carrier bearings and the ring gear, then transfer them to the new housing. Set the carrier bearing preload with the selective shim before you close the case, and check backlash and pattern on the final drive before the halves get sealed. Replace both carrier bearings while it is open - they have run in the same debris that killed the old housing.