Subaru Front Differential Retainer Socket 18630AA010

A toothed retainer socket that replaces the Subaru special tools 18630AA010, 18658AA020 and 499787000. It engages the slotted "sundial" side bearing retainers that hold the front differential carrier in Subaru manual transaxles, including retainers 38342AA020, 38342AA030, 38342AA130 and 38342AA150. Fitment covers the WRX (2002-2021), STI 2.5L 6-speed (2004-2021), Forester (1998-2013), Legacy (1990-2014) and Outback (1996-2014).

Those retainers do two jobs: they carry the axle shaft seals, and they set the differential side bearing preload and ring-and-pinion backlash. People try to spin them with a punch and hammer or a pair of screwdrivers, and the result is chewed-up slots, a retainer that will not come back to its marked position, and a seal leak or gear whine after the job. A socket that bites all the slots at once lets you back the retainer out and bring it back in under control.

On the bench or in the car: mark the retainer position against the case before you touch it, remove the axle and the lock plate, then drive the socket with a ratchet or breaker bar to back the retainer out. Replace the O-ring and seal, then thread the retainer back to your mark, or adjust it in and out to set backlash with a dial indicator if you are replacing bearings or gears. Reinstall the lock plate.

Forged alloy steel with an 8-point contact pattern so the load is spread across the retainer slots instead of one or two teeth. About 1 lb. Seals, O-rings and lock plates are not included.