U-Joint .688 -34/36 x .750 Smooth

The U-Joint .688 -34/36 x .750 Smooth steering universal joint by Woodward Machine is a critical component for vehicles requiring precision linkage between misaligned steering shafts. Whether you're restoring a classic truck, upgrading a off-road build, or repairing worn steering geometry on a daily driver, this single-joint assembly provides the articulation necessary to transmit rotational force while accommodating shaft runout and angular deflection. Steering u-joints are wear items that degrade over thousands of miles, causing slop, vibration, and reduced steering feedback—making replacement essential for safety and handling integrity.

This Woodward Machine u-joint features a 0.688-inch diameter shaft with a 34/36 spline input connection and a 0.750-inch (3/4 in) smooth output bore, crafted from durable steel in natural finish for corrosion resistance and longevity. The 34/36 spline configuration is commonly found in vintage domestic steering boxes and transfer cases, while the smooth 3/4-inch bore accepts standard shaft collars, flanges, or coupler fittings. At just 0.69 pounds and measuring 6.75 inches in overall length, this compact single-joint design minimizes parasitic weight while maintaining full rotational capacity across the typical steering column operating range, making it ideal for both OEM restoration and custom fabrication applications.

Mechanics and fabricators working on pre-1980s trucks, Jeeps, and muscle cars will find this u-joint essential for steering column rebuilds, angle corrections, and custom steering shaft extensions. Proper installation requires centering the joint within its operating envelope to minimize vibration and wear; misalignment accelerates needle bearing fatigue and reduces service life. Always inspect mating shafts for runout and damage before installation, and use quality steering-grade grease during assembly. This universal joint pairs seamlessly with vintage steering boxes, modern adaptors, and custom fabricated shafts where the 34/36 spline standard and 3/4-inch smooth bore are present.