Motive Gear 3984818 Differential Pinion Gear Thrust Washer GM 8.5/8.625

The Motive Gear 3984818 is a replacement differential pinion gear thrust washer engineered for GM 8.5 and 8.625 ten-bolt rear axle applications. Designed to exacting tolerances, this small but critical drivetrain component helps maintain proper pinion gear alignment and protects surrounding bearings from premature wear.

Key Features:

• Precision-fit design – Prevents excessive axial movement of the pinion gear, keeping it properly aligned along the shaft
• GM 8.5 / 8.625 compatible – Engineered specifically for GM ten-bolt differential cases without limited slip
• OEM part number cross-reference – Replaces GM OEM part #3984818; also replaces Yukon Gear YSPTW-047
• Quality construction – Built to Motive Gear's performance standards, developed through years of racing and drivetrain engineering experience
• Direct replacement – Drop-in fitment for straightforward installation during differential rebuild or repair

Motive Gear is a division of Midwest Truck and Auto Parts, offering a comprehensive line of drivetrain components including differential bearing kits, ring and pinion gear sets, transfer case parts, and axle shafts. The 3984818 pinion thrust washer is backed by Motive Gear's standard replacement parts warranty.