Pinion Bearing

Your transmission powers the differential through the driveshaft. The driveshaft is attached one end to the transmission, and on the other to the pinion gear of the differential. As the pinion spins, it turns the ring gear which powers the axles. The pinion bearing and race allow the pinion gear to spin smoothly. Low fluid levels can damage the ring and pinion gears inside the axle as well as the bearing and race. Damage to the pinion bearing can cause the pinion to emit a whirring noise when accelerating or slowing down. If you notice noises from your axle, differential, or driveshaft, check your bearings and U-joints. If you need a pinion bearing, race, U-joint, or other differential parts, visit O'Reilly Auto Parts.