National 710948 Automatic Transmission Extension Housing Seal

Overview of National 710948 Transmission Extension Housing Seal

The National 710948 automatic transmission extension housing seal is engineered for reliable sealing performance in Ford Super Duty trucks. Designed specifically for Ford E-350 Super Duty, F-250 Super Duty, and F-350 Super Duty models, this oil seal helps maintain transmission integrity by preventing fluid leaks.

• Inside diameter: 2.460 inches (62.5 mm)
• Outside diameter: 3.551 inches (90.2 mm)
• Flanged outside diameter: 3.839 inches (97.5 mm)
• Thickness: 0.472 inches (12 mm)
• Overall width with side lip: 1.969 inches (50 mm)
• Material: PTFE for enhanced durability and chemical resistance
• Helix type: Counter-clockwise spiral lip design for effective sealing
• Housing bore diameter: 3.543 inches (90 mm)

Technical Details and Specifications

The National 710948 seal is part of the 710900 series and is constructed from PTFE material, known for its resistance to heat, wear, and transmission fluids. The seal features a counter-clockwise spiral lip design that ensures a tight fit around the shaft, minimizing the risk of leaks. With an inside diameter of 2.460 inches and an outside diameter of 3.551 inches, it fits precisely within the transmission extension housing bore of 3.543 inches. The flanged outside diameter of 3.839 inches provides additional stability during installation, while the 0.472-inch thickness and 1.969-inch overall width with side lip contribute to a secure seal under operating conditions.

Compatible Vehicles and Applications

This automatic transmission extension housing seal is compatible with the following Ford models:

• Ford E-350 Super Duty
• Ford F-250 Super Duty
• Ford F-350 Super Duty

It is designed to replace worn or damaged seals in these vehicles, helping to maintain proper transmission fluid containment and prevent contamination.

Common Issues Addressed by the National 710948 Seal

• Prevents transmission fluid leaks from the extension housing
• Reduces risk of contamination entering the transmission system
• Minimizes wear on transmission components caused by fluid loss
• Helps maintain proper hydraulic pressure within the transmission
• Improves overall transmission reliability and longevity

Installation Notes and Tips

• Ensure the transmission extension housing bore is clean and free of debris before installation
• Verify the seal dimensions match the original part to ensure proper fit
• Use appropriate tools to press the seal evenly into the housing without damage
• Inspect the shaft for wear or damage that could affect seal performance
• Lubricate the seal lip lightly with transmission fluid prior to installation to reduce initial wear

Quality Assurance and Warranty

Manufactured by National, a recognized brand in sealing solutions, the 710948 transmission extension housing seal meets industry standards for durability and performance. The PTFE material and precision design contribute to consistent sealing under demanding conditions. While specific warranty details may vary, National typically offers coverage against manufacturing defects to ensure customer confidence in the product.