National 710718 Manual Transmission Output Shaft Seal

Overview of National 710718 Manual Transmission Output Shaft Seal

The National 710718 manual transmission output shaft seal is engineered to provide reliable sealing performance for a range of vehicles including BMW, Ford, and Rolls-Royce models. Designed with precision dimensions and durable materials, this seal helps maintain transmission integrity by preventing oil leaks and contamination.

• Inside diameter: 2.244 inches (57.000 mm)
• Outside diameter: 2.882 inches (73.200 mm)
• Thickness: 0.315 inches (8.000 mm)
• Material: Fluoro-elastomer for enhanced chemical and temperature resistance
• Helix type: Counter-clockwise spiral lip design for effective sealing
• Compatible housing bore: 2.874 inches (73.000 mm)

Technical Details and Material Specifications

This manual transmission output shaft seal from National, part number 710718, features a fluoro-elastomer sealing material known for its resistance to heat, oil, and wear. The counter-clockwise spiral lip design improves sealing efficiency by directing fluid back into the transmission, reducing leakage. With an inside diameter of 2.244 inches and an outside diameter of 2.882 inches, it fits precisely into the housing bore of 2.874 inches, ensuring a secure fit. The 0.315-inch thickness provides durability without compromising flexibility.

Compatible Vehicles and Applications

This output shaft seal is compatible with a variety of manual transmission vehicles, including luxury and heavy-duty models. It is suitable for use in:

• BMW 540i, 740i, 740iL, 750iL, 840Ci, 850Ci, and Z8
• Ford F-250 Super Duty, F-350 Super Duty
• GMC Sierra 2500 HD, Sierra 3500, Silverado 2500 HD, Silverado 3500
• Aston Martin DB7, Vanquish
• Bentley Arnage, Silver Seraph
• Jaguar XJR, XK8
• Rolls-Royce models

Common Issues Addressed by the National 710718 Seal

• Prevents oil leaks from the manual transmission output shaft
• Reduces contamination ingress that can damage transmission components
• Maintains proper lubrication within the transmission system
• Minimizes wear on the output shaft and surrounding components
• Helps avoid costly transmission repairs due to seal failure

Installation Notes and Tips

When installing the National 710718 output shaft seal, ensure the housing bore and shaft are clean and free of debris. Use appropriate tools to press the seal evenly into place without damaging the lip or sealing surface. Verify the seal orientation matches the counter-clockwise spiral lip design to optimize sealing performance. It is recommended to inspect the shaft for wear or damage before installation to ensure a proper seal.

Quality Assurance and Warranty

National manufactures the 710718 output shaft seal to meet industry standards for durability and performance. The use of fluoro-elastomer material ensures resistance to heat and chemical exposure common in transmission environments. While specific warranty details are not provided, National products typically adhere to strict quality control processes to ensure reliability in automotive applications.