InMotion WS2689S Wheel Seal - Rear

Rear Differential Pinion Seal for Buick-Oldsmobile Axle

The InMotion WS2689S is a rear differential pinion seal built for select Buick, Chevrolet, Oldsmobile, and Pontiac applications from 1971-1976. It uses nitrile material and precise dimensions to help maintain a tight seal at the pinion shaft, keeping contaminants out and gear oil in.

• Nitrile construction for sealing performance in driveline service
• Inside diameter: 1.875 in.; shaft diameter: 1.875 in.
• Outside diameter: 2.865 in.; housing bore: 2.877 in.
• Width: 0.49 in. for a compact pinion seal profile
• Fits rear axle applications with Buick-Oldsmobile axle or 9.375 in. ring gear, depending on vehicle
• Part number WS2689S for catalog and service matching

Detailed Fitment and Application

This differential pinion seal is used at the rear pinion area to help preserve differential lubrication and protect internal components from road debris and moisture. It is a direct service part for vehicles including the Buick LeSabre, Buick Riviera, Chevrolet Caprice, Chevrolet El Camino, Chevrolet Impala, Chevrolet Bel Air, Oldsmobile 98, Oldsmobile Delta 88, Oldsmobile Custom Cruiser, Pontiac Bonneville, Pontiac Catalina, Pontiac Laurentian, and Pontiac Parisienne. The WS2689S is specified for rear applications with Buick-Oldsmobile axle configurations and, on certain models, 9.375 in. ring gear setups.

This part cross-references Monroe Shocks & Struts (e.g., 172286, 182286) for the same application.

What It Helps Address

• Rear differential gear oil seepage at the pinion seal
• Contamination entering the pinion area from dirt or moisture
• Seal wear that can lead to driveline fluid loss
• Service replacement needs on classic Buick, Chevrolet, Oldsmobile, and Pontiac rear axles
• Maintenance for vehicles showing pinion-area leakage or dampness

Installation Notes and Tips

Verify the axle configuration, ring gear size, and seal dimensions before installation. Clean the housing bore and pinion shaft sealing surface thoroughly, and inspect the shaft for wear or scoring that could affect sealing. Confirm rear-position fitment against the vehicle listing before service. Part number WS2689S should be matched to the application details for the best fit.

Quality Assurance

InMotion manufactures this seal with precision-focused dimensions and nitrile material selection to support reliable sealing performance in differential service.