National 710558 Differential Pinion Seal - Front Outer

National 710558 Differential Pinion Seal

National 710558 is a differential pinion seal built for front outer applications on select Ram and Dodge Ram trucks with an AAM axle and 9.25-inch ring gear. It is engineered with a PTFE sealing material and a bi-directional lip design to help maintain a consistent seal at the pinion shaft.

Key Features

• PTFE seal material for low-friction sealing performance
• Bi-directional lip design
• Inside diameter: 2.125 in. / 53.975 mm
• Outside diameter: 2.920 in. / 74.166 mm
• Flanged outside diameter: 3.346 in. / 85.000 mm
• Thickness: 0.469 in. / 11.913 mm
• Overall width with side lip: 0.547 in. / 13.893 mm
• Housing bore: 2.914 in. / 74.016 mm
• Series 710500, Type 74

Detailed Description

This National differential pinion seal is designed for the front outer position and matches the dimensional requirements listed for the shaft and housing bore. National has supplied sealing solutions for decades, and this part reflects that focus with a PTFE construction and a bi-directional lip profile for controlled sealing at the pinion area. National 710558 cross-references Eastern Catalytic 20459 for the same application.

Compatible With 2011-2018 Ram 2500 front outer, 2011-2018 Ram 3500 front outer, 2003-2010 Dodge Ram 2500 front outer, 2003-2010 Dodge Ram 3500 front outer, and 2006-2008 Dodge Ram 1500 front outer when equipped with a 9.25-inch ring gear and AAM axle. For Ram 2500 and Ram 3500 front outer seal replacement, National 710558 provides the specified fitment and dimensions for these applications.

What It Helps Address

• Gear oil seepage at the front outer pinion seal
• Seal wear from age, heat, and driveline use
• Leak-related contamination around the differential housing
• Loss of sealing integrity at the pinion shaft area
• Service replacement needs on Ram and Dodge Ram front axle assemblies

Installation Notes and Tips

Verify the axle configuration, ring gear size, and front outer position before installation. Confirm the shaft diameter, housing bore, and seal width against the existing part to ensure proper seating. Clean the sealing surface and inspect the pinion area for wear or damage before installing the new seal.

Quality Assurance

National is recognized for premium sealing solutions and long-standing coverage in the automotive sealing market. This part is built to National’s dimensional and material standards for driveline sealing applications.