Product Description
Load Wheel Assembly
Frequently Asked Questions
Q: How is SU S9109-A different from SU S9109?
A: SU S9109 refers to the wheel component or a specific variant. SU S9109-A is the complete load wheel assembly with the polyurethane tread, finned aluminum hub, and pre-mounted and pre-pressed bearing configuration. The -A designation indicates it is supplied as a finished assembly ready for axle mounting. No additional bearing installation or pressing is required.
Q: Can I replace just the bearing on SU S9109-A, or must I replace the entire assembly?
A: The bearing on SU S9109-A is press-fit into the aluminum hub. If the bearing fails but the wheel tread and hub are undamaged, the bearing can be pressed out and a replacement installed. However, if the bearing is sealed (-2RS), you may not be able to remove it without damaging the hub. If the hub bore is damaged or the tread is worn, the entire assembly must be replaced.
Q: What is the torque specification for installing SU S9109-A on the axle?
A: Typical torque is 45 to 65 foot-pounds, depending on axle bolt diameter. Always consult your truck service manual for the exact specification. Under-tightening allows the wheel to slip and causes bolt loosening. Over-tightening can strip threads or damage the hub bore. Use a calibrated torque wrench and apply torque in a cross pattern if there are multiple bolts.
Q: How do I lubricate the greaseable version of SU S9109-A?
A: If your assembly has the -Z greaseable configuration, use a grease gun with general-purpose bearing grease (NLGI Grade 2). Apply grease to the external grease zerk fitting every 250 operating hours. A few pumps are sufficient; over-greasing can cause seals to fail and allow grease to splatter on the warehouse floor. If grease does not flow out when applying fresh grease, the fitting or bearing passage may be blocked.
Q: What surface conditions will cause SU S9109-A to wear faster?
A: Polyurethane treads wear faster on rough concrete, oily surfaces, and hot floors (above 120 degrees Fahrenheit). Continuous high-speed operation and constant sharp turns also accelerate tread wear. Indoor warehouse environments with smooth floors will extend lifespan to 2500 to 3000 operating hours. Outdoor or rough-surface use may reduce lifespan to 1500 hours or less.