National 240698 Manual Transmission Overdrive Solenoid Seal

Manual Transmission Overdrive Solenoid Seal for Borg-Warner Units

National 240698 is a manual transmission overdrive solenoid seal built for Borg-Warner R10 and R11 overdrive applications. It uses nitrile sealing material and precise dimensions to help maintain a tight seal at the solenoid housing in classic Chevrolet, Ford, Jeep, Mercury, and Pontiac drivetrains.

For restorations and transmission service work, National 240698 supports the sealing needs of Borg-Warner overdrive systems found in vehicles such as the Chevrolet Bel Air, Ford Mustang, and Jeep Wagoneer. This part cross-references Gates T332 for the same application.

Key Features

• Part number: National 240698
• Manual transmission overdrive solenoid seal for Borg-Warner R10 and R11 units
• Nitrile sealing material for oil resistance in transmission service
• Inside diameter: 0.312 in. / 7.920 mm
• Outside diameter: 0.635 in. / 16.130 mm
• Thickness/width: 0.175 in. / 4.450 mm
• Housing bore: 0.625 in. / 15.880 mm
• National 240000 series oil seal

Detailed Description

National 240698 is an oil seal specified as a manual transmission overdrive solenoid seal for Borg-Warner 2-speed overdrive systems. Its nitrile construction and measured dimensions are suited to the solenoid sealing interface, helping maintain proper fluid control in older manual transmission overdrive assemblies. National has supplied sealing solutions for more than 75 years and continues to apply that experience to service parts for legacy drivetrains.

Fitment includes 1950-1970 Chevrolet Bel Air, 1953-1970 Chevrolet Corvette, 1959-1970 Chevrolet Impala, 1964-1967 Ford Mustang, 1955-1967 Ford Thunderbird, 1963-1970 Jeep Wagoneer, and other Borg-Warner R10/R11-equipped applications. If you are searching for a National 240698 overdrive solenoid seal for a classic Chevrolet, Ford, or Jeep transmission, this part is listed for those service needs.

What This Part Helps Address

• Transmission fluid seepage at the overdrive solenoid seal area
• Seal wear in Borg-Warner R10 and R11 overdrive assemblies
• Loss of sealing integrity during manual transmission service
• Restoration work on classic Chevrolet, Ford, Jeep, Mercury, and Pontiac vehicles
• Replacement of a deteriorated nitrile oil seal in the solenoid bore

Installation Notes and Tips

Verify the transmission code and overdrive unit before ordering, since fitment varies by Borg-Warner R10B, R10C, R10E, R10F, R10L, R10Q, and R11 applications. Confirm the housing bore and shaft dimensions against the existing seal and inspect the solenoid bore for wear, corrosion, or debris before installation. Clean sealing surfaces thoroughly so the nitrile seal seats evenly and maintains proper contact.

Compatible vehicle examples include Fits 1950-1970 Chevrolet Bel Air, N/A with Borg-Warner R10B Transmission; 2 Speed; Fits 1964-1967 Ford Mustang, N/A with Borg-Warner R10L Transmission; 2 Speed; and Fits 1963-1970 Jeep Wagoneer, N/A with Borg-Warner R11 Transmission; 2 Speed.

Quality Assurance

National is a long-established sealing brand with a focus on transmission and engine sealing components. National 240698 is built as a service replacement oil seal for overdrive solenoid applications, with dimensions and material selection aligned to the listed Borg-Warner fitments.