Spicer Front Outer Axle Stub Shaft & Knuckle Vacuum Seal Kit for 1999-2004 Ford Super Duty (Dana 50 / 60, Single Side)

Restore factory-spec structural strength, eliminate severe front drivetrain vibration, and refresh your automatic locking hub vacuum boundaries with this genuine Spicer Front Outer Axle Stub Shaft & Knuckle Vacuum Seal Kit. Specially bundled to provide a streamlined repair package for 1999–2004 Ford F-250 and F-350 Super Duty trucks, this single-side combination replaces a twisted or compromised outer axle shaft while ensuring an airtight wheel end assembly.

On solid-axle Ford platforms, the outer stub shaft takes the brunt of high-torque drivetrain loads under heavy towing, commercial fleet hauling, or off-road use. Over high mileage, or following a sudden universal joint failure, the axle shaft's yoke ears can bend, stretch, or crack, preventing the U-joint snap rings from seating safely and threatening a total hub failure. Concurrently, removing the outer axle assembly destroys the massive main knuckle seal, which is a single-use component responsible for sustaining the vacuum required to trigger your dashboard-controlled Electronic Shift-on-the-Fly (ESOF) automatic locking hubs.

This original equipment manufacturer (OEM) combination service package provides a factory-correct solution to overhaul one front steering knuckle station. Sourcing genuine Spicer components guarantees exact original manufacturing blueprints are met, offering factory-matched spline depth, induction-hardened metallurgy, and the precise rubber multi-lip design required to maintain an airtight vacuum seal under extreme steering deflection.

Kit Contents (Services One Steering Knuckle Side):

• (1) Genuine Spicer 30-Spline Outer Axle Stub Shaft (Part # 47750 / 2002638)

• (1) Premium Main Outer Axle Shaft to Knuckle Vacuum Seal (Part # 50491 / 2023068)

Kit Highlights:

• Targeted Overhaul Solution: Pairs a brand-new outer stub axle shaft with its primary main vacuum knuckle face seal to minimize components when your universal joints and secondary O-rings are still in serviceable condition.

• Restores Automatic 4WD Operation: Includes the critical large-diameter vacuum seal to properly isolate the knuckle hub cavity, bringing your automatic dashboard 4WD engagement back to peak functionality.

• Genuine Spicer OEM Quality: Forged, induction-hardened, and precision-machined by the vehicle's original equipment axle supplier to guarantee perfect structural metallurgy and exact dimensional alignment.

• Prevents Axle Walk & Play: Re-establishes factory-spec tolerances inside your front wheel end configuration, stopping dangerous axle movement that accelerates hub assembly wear.

Vehicle & Axle Fitment:

• Axle Profiles: Open-Knuckle Solid/Monobeam Front Axles: Dana 50 and Dana 60 configurations with vacuum-operated automatic locking hubs.

• Ford Models: 1999, 2000, 2001, 2002, 2003, and 2004 Ford F-250 Super Duty and F-350 Super Duty 4WD trucks, alongside 2000–2005 Ford Excursion 4x4 vehicles.

• Position: Front Steering Knuckle Wheel End Station (Fits Left or Right Side — Sold Individually)