U-Joint Size Identification

U-Joint Identification Guide – Measure & Match with Confidence

Whether you're repairing, replacing, or upgrading your driveline, identifying the correct universal joint (U-joint) is critical for proper fitment and long-term reliability. At Tom Wood's, we've made the process easier with our new U-Joint Size Measure & Match App.

Use the Tool: Measure & Match Your U-Joint

Our interactive tool walks you through identifying your U-joint based on:

• Cap diameter

• U-joint width

• Clip type (inside or outside)

• Common part numbers and vehicle applications

Why U-Joint Sizing Matters

U-joints come in dozens of sizes and styles—from Spicer 1310 and 1350 series to metric joints used in many import vehicles. Even a few thousandths of an inch in cap diameter can make the difference between a secure fit and premature failure.

How to Manually Measure Your U-Joint

For best results, use calipers. A measuring tape can work, but you'll need to convert fractions to decimals (e.g., 3 5/8" becomes 3.625").

Take two key measurements:

• Cap Diameter – Measure the outside diameter of one bearing cap.

• U-Joint Width – Measure from the outside of one cap to the outside of the opposite cap, across the joint.

Also determine the clip type:

• Inside clips (snap rings) sit inside the yoke ears.

• Outside clips rest on the outside of the bearing caps.

Common  U-Joint Series and Applications