National 220918 Automatic Transmission Input Shaft Seal

Automatic Transmission Input Shaft Seal

National 220918 is an automatic transmission input shaft seal built with nitrile material for reliable sealing performance in the transmission case. It is a metric oil seal with precise dimensions for applications that require a 9.0 mm shaft and an 18.0 mm housing bore.

Compatible with a wide range of Honda, Acura, and Isuzu vehicles, this seal supports service work on Honda Civic, Honda Accord, and Acura Integra transmission assemblies. The National 220918 part number is also referenced by OE and aftermarket cross numbers for the same application.

Key Features

• Nitrile construction for transmission sealing applications
• Metric oil seal design
• Inside diameter: 0.354 in. / 9.0 mm
• Outside diameter: 0.717 in. / 18.2 mm
• Housing bore: 0.709 in. / 18.0 mm
• Width: 0.276 in. / 7.0 mm
• National 220918 part number for easy identification

Detailed Description

National 220918 is an automatic transmission input shaft seal engineered as a metric oil seal for transmission sealing service. Its nitrile material and compact dimensions help provide a proper fit at the input shaft and housing bore interface, where maintaining fluid control is critical. This seal is used across many Honda and Acura applications, including Honda Civic, Honda Accord, and Acura Integra models, making it a practical replacement for transmission maintenance on older and later model vehicles.

This part cross-references ATP HO-23 and SKF 6641 for the same application.

Vehicle Fitment

• Fits 2006-2014 Honda Civic, N/A
• Fits 1992-2000 Honda Civic, N/A
• Fits 2013-2014 Honda Fit, N/A
• Fits 2009-2010 Honda Fit, N/A
• Fits 2011-2012 Honda Fit, N/A, with Honda M5PA Transmission
• Fits 2010-2011 Acura CSX, N/A
• Fits 2006-2009 Acura CSX, N/A, with Honda MPMA Transmission
• Fits 2002-2006 Honda CR-V, N/A
• Fits 1995-2002 Honda Accord, N/A
• Fits 1993 Honda Accord, N/A
• Fits 1991 Honda Accord, N/A
• Fits 1991-2001 Acura Integra, N/A
• Fits 1999-2000 Acura EL, N/A, with Automatic Transmission; 4 Speed
• Fits 1997-1999 Acura CL, N/A
• Fits 1996-1999 Isuzu Oasis, N/A
• Fits 1997-1998 Acura EL, N/A
• Fits 1995-1998 Honda Odyssey, N/A
• Fits 1993-1997 Honda Civic del Sol, N/A
• Fits 1992-1996 Honda Prelude, N/A

Installation Notes

Confirm shaft diameter, housing bore, and seal width before installation. Clean the sealing surface thoroughly and inspect the transmission input shaft for wear, scoring, or contamination that could affect sealing performance. For Honda and Acura transmission service, verify transmission code notes such as Honda M5PA or MPMA where listed in the fitment data.

Quality Assurance

National has supplied sealing solutions for more than 75 years and continues to develop sealing products for modern vehicle service needs. Part number 220918 is backed by National’s long-standing focus on transmission and engine sealing applications.