InMotion WS8660S Wheel Seal - Rear

Rear Differential Pinion Seal for Select Ford, Jeep, and GM Applications

The InMotion WS8660S is a rear differential pinion seal built with nitrile sealing surfaces and a precision case design to help keep gear oil contained while blocking dirt and moisture from entering the differential. It is a direct-fit sealing component for a wide range of rear axle applications, including Ford Mustang, Jeep Cherokee, and Chevrolet S10 models.

Key Features

• Nitrile sealing surface material for dependable fluid sealing
• SAE 1008 spring material for consistent sealing pressure
• SAE 1070 seal case material for structural support
• Dimensions: 1.399 in shaft diameter, 2.292 in housing bore, 0.460 in width
• External markings: 1.399 x 2.292 x 0.460
• Rear-position application across a broad range of driveline setups
• Part number WS8660S for catalog and service lookup

Detailed Description

Built for rear axle service, this seal helps maintain the integrity of the differential pinion area by creating a tight barrier at the housing interface. The nitrile sealing surface is selected for oil resistance, while the spring and case materials support stable sealing performance under driveline load. With confirmed dimensions of 1.375 in inside diameter, 2.299 in outside diameter, and 0.46 in width, WS8660S is specified for applications that require an exact match to the pinion seal profile. This part number WS8660S is listed for numerous rear differential applications across Ford, Jeep, Chevrolet, GMC, Mazda, Pontiac, and other platforms.

Compatible vehicle examples include Ford Crown Victoria rear, Ford Ranger rear with 7.5in ring gear, Jeep Cherokee rear with Spicer 35C axle, and Chevrolet Camaro rear. This part cross-references Monroe Shocks & Struts (e.g., 172286, 182286) for the same application.

What It Helps Address

• Gear oil seepage at the differential pinion area
• Contamination from road debris and moisture entering the axle assembly
• Seal wear that can lead to driveline fluid loss
• Noise or driveline concerns associated with low differential lubricant level
• Service needs on rear axle pinion seal replacement jobs

Installation Notes and Tips

Verify shaft diameter, housing bore, and seal width before installation to confirm the correct match for the axle assembly. Clean the sealing surface and housing bore thoroughly, and inspect the pinion yoke or shaft surface for wear before pressing in the new seal. For fitment-specific service, confirm the rear axle configuration on vehicles such as Ford Mustang, Jeep Grand Cherokee, and Chevrolet S10 before ordering.

Quality Assurance

InMotion manufactures this seal with precision-focused materials and dimensions to support reliable differential sealing in service applications. The WS8660S is engineered for consistent fitment across the listed rear axle platforms and is built to meet the demands of everyday driving and off-road use.

Compatible With

• Fits 1992-2011 Ford Crown Victoria, Rear
• Fits 1983-2011 Ford Ranger, Rear with 7.5in Ring Gear
• Fits 1981-2011 Lincoln Town Car, Rear
• Fits 1980-2011 Mercury Grand Marquis, Rear
• Fits 2001-2009 Mazda B2300, Rear
• Fits 1994-2009 Mazda B4000, Rear
• Fits 1994-2007 Mazda B3000, Rear
• Fits 1995-2005 Chevrolet Blazer, Rear with Axle Code K
• Fits 1992-2005 GMC Jimmy, Rear with Axle Code K
• Fits 1992-2004 Chevrolet S10, Rear with Axle Code K
• Fits 1984-2004 Ford Mustang, Rear
• Fits 1992-2004 GMC Sonoma, Rear with Axle Code K
• Fits 2003-2004 Mercury Marauder, Rear
• Fits 1991-2002 Chevrolet Camaro, Rear
• Fits 1992-2002 Pontiac Firebird, Rear
• Fits 1990-1999 Jeep Cherokee, Rear with Spicer 35C Axle
• Fits 1994-1998 Jeep Grand Cherokee, Rear with Spicer 35C Axle
• Fits 1994-1995 Jeep Wrangler, Rear with Spicer 35C Axle

Additional coverage extends across many rear axle service applications from 1963-2011, making WS8660S a useful catalog match for differential pinion seal replacement on select Ford, Jeep, Chevrolet, GMC, Mazda, Pontiac, Buick, Cadillac, Lincoln, Mercury, Oldsmobile, Isuzu, Chrysler, and Dodge vehicles.