Equip your semi to be Ready for the Road Aheadâ„¢, with the Spicer 1550 Series Greaseable Universal Joint, a crucial component for the effective transfer of engine power. By using a flexible cross-shaped design, this universal joint is able to transfer power from the drive shaft to the wheels while the drive shaft moves up or down with the suspension. Constructed with precise measurements and a durable body to resist weathering, corrosion, and rust.