National 100552 Differential Pinion Seal - Rear or Rear Outer

National 100552 Differential Pinion Seal

National 100552 is a differential pinion seal built for rear and rear outer applications on select Ford, Lincoln, Mazda, and Mercury vehicles. It uses a fluoro-elastomer sealing material and a bi-directional lip design to help maintain a consistent seal at the pinion shaft.

Key Features

• Part number: National 100552
• Part description: oil seal / differential pinion seal
• Fluoro-elastomer construction for sealing performance
• Bi-directional lip design
• Inside diameter: 1.844 in. / 46.840 mm
• Outside diameter: 2.872 in. / 72.950 mm
• Flanged outside diameter: 3.228 in. / 82.000 mm
• Thickness: 0.425 in. / 10.800 mm
• Housing bore: 2.865 in. / 72.770 mm
• Overall width with side lip: 0.472 in. / 12.000 mm

Detailed Description

National has supplied sealing products for more than 75 years, and the 100552 differential pinion seal reflects that focus on dimensional accuracy and modern sealing materials. This seal is specified for applications such as the Ford Explorer rear, Ford Taurus rear, Ford Edge rear outer, Lincoln MKX rear outer, and Mercury Mariner rear outer, along with other listed Ford, Lincoln, Mazda, and Mercury fitments. If you are replacing a leaking pinion seal on a Ford Explorer, Ford Taurus, or Lincoln MKX, National 100552 provides the correct size and seal profile for the application.

This part cross-references Continental 49931 for the same application.

What It Helps Address

• Gear oil seepage at the differential pinion shaft
• Fluid loss around the pinion seal area
• Contamination from a worn or hardened seal lip
• Noise or driveline issues caused by low differential fluid
• Seal replacement during rear differential service

Installation Notes and Tips

• Verify shaft, housing bore, and seal dimensions before installation.
• Inspect the pinion yoke and sealing surface for wear, grooves, or corrosion.
• Clean the bore thoroughly so the seal seats evenly.
• Follow the vehicle service procedure for pinion preload and torque settings.
• Confirm the vehicle uses the listed rear or rear outer position before ordering.

Quality Assurance

National is a long-established sealing brand with a reputation built on premium sealing solutions and ongoing product development for current vehicle platforms. National 100552 is engineered to meet the dimensional and material requirements of the listed Ford, Lincoln, Mazda, and Mercury applications.

Compatible Vehicles

• Fits 2011-2018 Ford Explorer, Rear
• Fits 2008-2018 Ford Taurus, Rear
• Fits 2013-2016 Lincoln MKS, Rear
• Fits 2009-2013 Ford Flex, Rear
• Fits 2013 Lincoln MKT, Rear
• Fits 2007-2012 Ford Edge, Rear Outer
• Fits 2001-2012 Ford Escape, Rear Outer, with 6.85 (in) Ring Gear; with Spicer 28 Axle; Independent Rear Suspension
• Fits 2007-2012 Ford Fusion, Rear
• Fits 2009-2012 Lincoln MKS, Rear Outer
• Fits 2010-2012 Lincoln MKT, Rear Outer
• Fits 2007-2012 Lincoln MKX, Rear Outer
• Fits 2007-2012 Lincoln MKZ, Rear Outer
• Fits 2008-2011 Mazda Tribute, Rear Outer, with 6.85 (in) Ring Gear; with Spicer 28 Axle; Independent Rear Suspension
• Fits 2001-2006 Mazda Tribute, Rear Outer, with 6.85 (in) Ring Gear; with Spicer 28 Axle; Independent Rear Suspension
• Fits 2005-2011 Mercury Mariner, Rear Outer, with 6.85 (in) Ring Gear; with Spicer 28 Axle; Independent Rear Suspension
• Fits 2007-2011 Mercury Milan, Rear
• Fits 2008-2009 Ford Taurus X, Rear
• Fits 2008-2009 Mercury Sable, Rear