4-28-417 – Weld Yokes – 1550 Series – Butt Dia 3.321″ – Tube Dia Wall 3.500×0.095

• 1550 series: 1.375" cap diameter U-joint -- larger than 1480 (also 1.375" cap) but different body geometry; verify the series designation on replacement joints
• 3.500" x 0.095" tube -- medium-wall specification for medium-duty commercial applications
• 3.321" butt diameter provides positive centering in the 3.310" bore (3.500" - 2x0.095" = 3.310"; 3.321" butt creates 0.011" interference)
• 2.688" CL-to-weld -- consistent Spicer commercial standard for this series and tube class
• Spicer OEM quality; appropriate for Class 4-6 truck and commercial van drivetrain repairs

A useful verification: if you have an existing 1550-series driveshaft and are unsure whether the weld yoke is a 1550 or the closely related 1480, measure the yoke ear bore diameter. 1550 uses a cap diameter of 1.375", while 1480 also uses 1.375" -- the distinguishing feature is in the journal length and bearing cup depth, not the external cap OD. Always pull the U-joint and compare to the Spicer catalog spec for the series before purchasing a replacement joint.