Timken 4765 Automatic Transmission Extension Housing Seal - Rear

Timken 4765 Transmission Seal

Timken 4765 is an automatic transmission extension housing seal built to control fluid loss and keep contaminants out of the transmission assembly. It is a direct-fit service part for select Ford and Mercury applications, including Ford E-150, E-250, E-350 Super Duty, F-150, Explorer, Ranger, Expedition, and Mercury Mountaineer models.

Key Features

• Precision sealing design helps retain lubricant and block debris entry
• Reinforced outer case helps reduce installation damage and improve durability
• Ribbed rubber inner diameter helps seal minor shaft imperfections and supports positive seating
• Internal contamination exclusion system helps limit debris penetration that can lead to leakage
• Vent holes promote lubricant flow around the seal lip to help manage heat build-up

Detailed Description

Built for transmission service, Timken 4765 is engineered for extension housing and output shaft sealing applications where fluid retention and contamination control are critical. This seal is used across a wide range of Ford truck, van, and SUV platforms, including 1994-2014 Ford E-150, 2005-2014 Ford E-250, 2007-2014 Ford E-350 Super Duty, 2004-2010 Ford F-150, 1996-1999 Ford Explorer, and 1997-2001 Mercury Mountaineer applications. Timken 4765 is a practical choice when servicing a leaking transmission output shaft seal on Ford E-150, Ford F-150, or Ford Explorer drivetrains.

This part cross-references National Oil Seals 4765 for the same application.

What It Helps Fix

• Transmission fluid seepage at the extension housing or output shaft area
• Contamination entering the seal area during normal road use
• Leakage caused by minor shaft surface imperfections
• Heat-related seal wear from poor lubricant circulation around the lip
• Service issues on Ford and Mercury vehicles with worn output shaft sealing surfaces

Installation Notes and Tips

Inspect the shaft and housing for scoring, corrosion, or burrs before installation. Clean the sealing surface thoroughly and verify the seal is seated squarely in the bore to avoid premature leakage. Confirm the application by year, make, model, and transmission configuration before replacing the seal.

Quality Assurance

Timken designs oil and grease seals with precision sealing geometry and contamination control features for service reliability in drivetrain applications.