Spicer 5-3212X 1555WJ / 1550 Series Solid-Cross Maintenance-Free Universal Joint (ISR Style)

Restore uncompromised torque handling, eliminate harsh driveline vibrations, and protect your commercial or medium-duty truck from costly road failures with this genuine Spicer 5-3212X 1555WJ / 1550 Series Universal Joint. Engineered as a premium, original equipment manufacturer (OEM) replacement component, this Inside Snap Ring (ISR) universal joint is designed to handle extreme rotational loads on high-capacity driveshaft assemblies under heavy vocational service.

On medium-duty and commercial vehicles, the driveshaft operates under massive, continuous stress, transferring raw torque from the transmission to the drive axles under heavy payloads. Over long service hours, high highway mileage, or demanding stop-and-go commercial routes, the internal needle bearings within the u-joint bearing caps naturally experience wear or grease breakdown. A failing universal joint will introduce slack into the driveline, manifesting as a loud clunking noise when shifting from reverse to drive, persistent high-speed chassis vibrations, or a squeaking sound that scales with vehicle speed. Left unaddressed, a seized joint can experience a catastrophic structural failure, throwing the driveshaft from the vehicle and causing extensive secondary damage to the transmission housing, air lines, and chassis frame rails.

Manufactured by Dana Spicer, the global benchmark in drivetrain engineering, the 5-3212X is built from high-strength, cold-formed alloy steel with a solid core architecture. This premium, non-greaseable "Life Series" configuration eliminates internal stress-fracture pathways common to drilled grease-channel designs, maximizing pure torsional strength. It comes factory-packed with a proprietary synthetic lubricant and is completely sealed with advanced multi-lip elastomeric boot seals, permanently locking out road grime, water, salt, and dust while eliminating the need for manual greasing intervals.

Kit Contents:

• (1) Genuine Spicer 1555WJ / 1550 Series Solid-Cross Universal Joint

• (4) Precision Ground Bearing Cups with Pre-Packed Synthetic Lubricant

• Complete Set of Heavy-Duty Internal Inside Snap Rings

Kit Highlights:

• Maintenance-Free Life Series: Permanently sealed design keeps premium synthetic grease locked inside the journals, maximizing service life and eliminating routine maintenance downtime.

• Cold-Formed Solid Cross Rigidity: Forged from premium-grade steel without internal grease passages, providing maximum structural density and resistance to twisting or shattering under peak torque loads.

• Premium Multi-Lip Sealing: Outfitted with robust elastomeric seals and custom thrust washers to maintain an absolute barrier against water entry, road brine, and environmental debris.

• Flawless OEM Fitment: Machined to exact factory tolerances to guarantee a precise press-fit into the driveshaft yoke, preventing rotational runout and restoring smooth operation.

Drivetrain & Series Specifications:

• Yoke Retention Style: Inside Snap Ring (ISR) / Internal Lock-Up. Fits yokes designed for internal retaining rings located on the inner side of the yoke ears.

• Series Identification: 1555WJ / 1550 Series Architecture.

• Bearing Cup Diameter: 1.375 inches.

• Common Applications: Medium-duty delivery trucks, commercial box trucks, dump trucks, utility vehicles, school buses, and specialized high-torque industrial machinery utilizing 1550/1555WJ series drivelines.