National 2503N Manual Transmission Input Shaft Seal

Manual Transmission Input Shaft Seal

National 2503N is a manual transmission input shaft seal built for Ford and Mercury applications that use the specified Ford Type B, Type E, or Type F transmissions. It uses a polyacrylate sealing material and a clockwise-spiral lip design to help maintain a consistent seal at the input shaft.

For buyers searching for a Ford Mustang manual transmission input shaft seal or a Mercury Capri transmission seal, this part number 2503N matches the listed applications and dimensions. The Redi-Coat surface treatment is included in the design for easier sealing performance during service.

Key Features

• Polyacrylate construction for sealing durability in transmission service.
• Clockwise-spiral lip design for controlled sealing action at the shaft.
• Redi-Coat finish for improved sealing contact during installation.
• Specified for Ford Type B, Type E, and Type F transmission applications.
• National 2503N replacement seal for manual transmission input shaft service.

Detailed Description

This National 2503N oil seal is engineered as a manual transmission input shaft seal with a 1.100-inch shaft diameter, 1.578-inch outside diameter, and 0.308-inch width. The seal is listed in National’s 2000 series and is identified as Type 48. National has supplied sealing solutions for more than 75 years, and this part reflects that focus on transmission sealing components. It is a direct fit for the listed Ford and Mercury vehicles with the matching transmission type, including Ford Mustang and Mercury Capri applications.

This part cross-references Anchor 2938 and CSF 10930 for the same application.

What It Is Used For

• Stopping transmission fluid seepage at the input shaft.
• Replacing a worn or hardened manual transmission seal.
• Addressing leaks around the transmission housing bore.
• Restoring sealing performance after clutch or transmission service.
• Supporting proper lubrication retention inside the transmission.

Installation Notes and Tips

Verify the transmission type before ordering, since fitment varies by Ford Type B, Type E, and Type F applications. Confirm shaft and housing dimensions against the service requirements for the vehicle. Clean the bore and shaft surface thoroughly before installation to help the seal seat correctly.

Quality Assurance

National has been a recognized sealing brand for more than 75 years and continues to develop sealing solutions for modern vehicle service needs. Part number 2503N is built to National’s sealing standards for the listed manual transmission applications.