National 4525V Differential Pinion Seal - Rear Outer

National 4525V Differential Pinion Seal

National 4525V is a differential pinion seal built for rear outer applications that require a precise seal around the pinion shaft. It uses fluoro-elastomer material and OE-style dimensions to help maintain proper sealing in demanding driveline service.

Key Features

• Part number: 4525V
• Part description: oil seal / differential pinion seal
• Material: fluoro-elastomer for sealing performance in driveline use
• Inside diameter: 2.500 in. / 63.500 mm
• Outside diameter: 4.040 in. / 102.620 mm
• Thickness: 0.419 in. / 10.643 mm
• Overall width with side lip: 0.630 in. / 16.000 mm
• Housing bore: 4.035 in. / 102.490 mm
• Series: 4000, Type 72

Detailed Description

National 4525V is engineered for rear outer differential pinion seal applications where the shaft and housing dimensions must match closely. The seal measures 2.500 inches inside diameter, 4.040 inches outside diameter, and 0.419 inches in width, with a 4.035-inch housing bore and fluoro-elastomer construction. National has supplied sealing solutions for more than 75 years, and this design reflects that focus on modern driveline sealing requirements. This part cross-references SKF 25140 for the same application.

Compatible With 2001 Dodge Ram 3500, rear outer; 1992-2000 Chevrolet C3500, rear outer; 1994-2000 Dodge Ram 2500, rear outer; 1994-2000 Dodge Ram 3500, rear outer; 1999-2000 Ford F-350 Super Duty, rear outer; 1992-2000 GMC C3500, rear outer; 1989-1999 Chevrolet P30, rear outer; and 1989-1999 GMC P3500, rear outer. These fitments include 11mm ring gear and Spicer 80 axle applications where noted.

Common Uses

• Stops gear oil leakage at the differential pinion area
• Addresses seepage around the rear outer pinion shaft seal
• Helps restore sealing on worn or aging axle assemblies
• Supports service on Spicer 80 axle applications with 11mm ring gear notes
• Replaces a damaged or hardened pinion seal during driveline repair

Installation Notes

Verify shaft diameter, housing bore, and seal width before installation. Clean the seal bore and pinion surface thoroughly, and inspect the yoke or shaft for wear that could affect sealing. Confirm the vehicle application against the listed fitment, especially on Dodge Ram 2500, Dodge Ram 3500, Chevrolet C3500, GMC C3500, Ford F-350 Super Duty, Chevrolet P30, and GMC P3500 models.

Quality Assurance

National is a long-established sealing brand with more than 75 years of experience in sealing technology. The 4525V is built as a precision driveline seal for applications that demand accurate dimensions and durable fluoro-elastomer construction.