National 4674N Automatic Transmission Output Shaft Seal - Right

Overview of National 4674N Automatic Transmission Output Shaft Seal

The National 4674N automatic transmission output shaft seal is engineered to provide reliable sealing performance for select Buick, Cadillac, Oldsmobile, and Pontiac models. Designed with precision dimensions and durable materials, this seal helps maintain transmission fluid integrity and prevents leaks in critical drivetrain components.

• Inside diameter: 1.605 inches (40.770 mm)
• Outside diameter: 2.804 inches (71.220 mm)
• Flanged outside diameter: 3.061 inches (77.750 mm)
• Thickness: 0.364 inches (9.250 mm)
• Bi-directional lip design for effective sealing
• Constructed from polyacrylate material for durability
• Redicoat surface treatment for enhanced wear resistance
• Compatible with housing bore diameter of 2.795 inches (71.000 mm)

Technical Details and Material Specifications

The National 4674N output shaft seal features a bi-directional helix lip design that ensures effective sealing against fluid leakage in both rotational directions. Its polyacrylate construction offers resistance to heat and transmission fluids, contributing to long service life. The seal’s precise dimensions, including a 1.605-inch inside diameter and a 2.804-inch outside diameter, make it suitable for specific automatic transmission output shafts. The Redicoat coating enhances the seal’s surface durability, reducing wear and extending operational reliability.

Compatible Vehicle Applications

This automatic transmission output shaft seal is compatible with various GM vehicles, including Buick Allante and Lucerne, Cadillac DeVille, DTS, Eldorado, and Seville, Oldsmobile Aurora and Bonneville, and Pontiac models. The part number 4674N ensures proper fitment and function within these transmissions, maintaining fluid containment and preventing contamination.

Common Issues Addressed by the 4674N Seal

• Prevents transmission fluid leaks from the output shaft area
• 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
• Prevents premature transmission failure due to seal degradation

Installation Notes and Tips

When installing the National 4674N output shaft seal, ensure the housing bore and shaft surfaces are clean and free of debris. Use appropriate tools to avoid damaging the seal lips during installation. Verify the seal orientation matches the bi-directional lip design for optimal sealing performance. Lubricate the seal with transmission fluid before installation to reduce initial wear. Confirm fitment compatibility with the specific Buick, Cadillac, Oldsmobile, or Pontiac model prior to installation.

Quality Assurance and Warranty Information

National’s 4674N transmission output shaft seal is manufactured to meet industry standards for durability and performance. The use of polyacrylate material and Redicoat treatment ensures resistance to heat and fluid exposure. While specific warranty details may vary, National typically provides coverage against manufacturing defects to support product reliability and customer confidence.