National 710254 Transfer Case Companion Flange Seal

Transfer Case Oil Seal for Toyota and Lexus 4WD

National 710254 is a transfer case companion flange seal built with nitrile material for sealing the shaft area in select Toyota and Lexus 4WD applications. It is specified as an oil seal with metric dimensions and is used in transfer cases that require a 23.0 mm shaft size and a 32.2 mm outside diameter.

Key Features

• Nitrile sealing material for oil resistance in transfer case service
• Metric dimensions: 23.0 mm inside diameter, 32.2 mm outside diameter, 5.5 mm width
• Designed for transfer case companion flange sealing applications
• National 710254 part number for direct reference and ordering
• Cross-reference: BBB Industries 9005

Detailed Description

National 710254 is a transfer case companion flange seal used to help maintain a proper seal at the transfer case output area. The seal measures 0.905 in. inside diameter, 1.268 in. outside diameter, and 0.217 in. width, with a 1.260 in. housing bore. Its nitrile construction is suited for oil sealing duties in drivetrain service, and the metric sizing makes it a precise match for the listed applications. This part cross-references BBB Industries 9005 for the same application. National 710254 is a direct-fit sealing solution for many Toyota 4Runner, Tacoma, Tundra, FJ Cruiser, Sequoia, Pickup, T100, Previa, and Lexus GX models equipped with the specified Aisin transfer cases.

What It Helps Address

• Transfer case fluid seepage at the companion flange area
• Oil leakage around the output shaft seal surface
• Contamination from worn or hardened sealing material
• Loss of sealing integrity in high-mileage 4WD transfer cases
• Service replacement for damaged or leaking transfer case seals

Installation Notes and Tips

• Verify transfer case type before ordering; this seal is listed for specific Aisin VF and RF series transfer cases.
• Confirm shaft diameter, housing bore, and width against the removed seal or service data.
• Inspect the flange and shaft sealing surface for wear, grooves, or corrosion before installation.
• Clean the bore and sealing surface thoroughly to support proper seal seating.
• Use the exact application notes for Toyota 4Runner, Tacoma, Tundra, FJ Cruiser, Sequoia, Pickup, T100, Previa, GX470, and GX460 fitment.

Quality Assurance

National has supplied sealing products for more than 75 years and continues to develop sealing solutions for modern vehicles. Part number 710254 reflects that OE-style sealing focus for transfer case service in Toyota and Lexus drivetrains.