National 100537 Drive Axle Shaft Seal - Rear

Drive Axle Shaft Seal for IRS Applications

National 100537 is a metric drive axle shaft seal built for rear axle service on select Ford, Lincoln, and Mercury vehicles with independent rear suspension. It uses fluoro-elastomer sealing material and a Redicoat finish to support a precise seal at the axle shaft and housing interface.

For rear axle repair on Ford Mustang, Ford Explorer, Lincoln Navigator, and Mercury Mountaineer applications, this seal is sized for the specified housing bore and shaft dimensions. National 100537 is a direct-fit sealing component for vehicles that require a Viton-type rear drive axle shaft seal.

Key Features

• Part number: 100537
• Drive axle shaft seal / oil seal for rear axle service
• Fluoro-elastomer sealing material for demanding driveline conditions
• Metric dimensions for accurate housing and shaft fit
• Inside diameter: 1.811 in. / 46.000 mm
• Outside diameter: 2.881 in. / 73.177 mm
• Thickness: 0.472 in. / 12.000 mm
• Flanged outside diameter: 3.228 in. / 82.000 mm
• Housing bore: 2.874 in. / 73.000 mm
• Redicoat finish

Detailed Description

National 100537 is part of National’s 100000 series of sealing products and is engineered for rear drive axle shaft sealing in IRS-equipped vehicles. The seal’s metric sizing, fluoro-elastomer construction, and Redicoat surface treatment support consistent sealing at the axle shaft bearing area where gear oil retention is critical. This part number 100537 is listed for applications including 2001-2004 Ford Mustang rear, 2002-2005 Ford Explorer rear, 2002-2006 Ford Expedition rear, 2002-2006 Lincoln Navigator rear, and 2002-2005 Mercury Mountaineer rear.

National has focused on sealing solutions for more than 75 years, and this seal reflects that experience with a design intended for modern driveline requirements. This part cross-references Bosch 18106 for the same application.

What It Helps Repair

• Rear axle gear oil leakage at the drive axle shaft seal
• Fluid seepage around the axle shaft bearing area
• Seal wear on IRS rear differential applications
• Noise or contamination concerns caused by compromised sealing surfaces
• Service replacement for Viton-type rear axle seal applications

Installation Notes and Tips

• Verify the housing bore, shaft diameter, and seal thickness before installation.
• Inspect the axle shaft and seal bore for scoring, corrosion, or debris that could affect sealing.
• Confirm rear-position fitment and ring gear configuration before ordering.
• Use clean installation practices to avoid damaging the sealing lip or Redicoat surface.
• Match the application to the listed vehicle, year, and rear axle notes, including independent rear suspension and ring gear size.

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 100537 is manufactured as a precision driveline seal for the listed Ford, Lincoln, and Mercury rear axle applications.