Product Description
Load Wheel Assembly
Frequently Asked Questions
Q: Is the SU 339-A assembly a plug-and-play replacement or does it require modification?
A: The SU 339-A is a direct replacement assembly requiring no modification. The bearing, spacer, and fastener specifications remain standard across Yale, Hyster, and Nissan equipment. Simply remove the old assembly and slide the new one onto the axle. No tools beyond a 19mm wrench and rubber mallet are needed.
Q: What is the proper axle bolt torque specification for the SU 339-A assembly?
A: Tighten the axle bolt to 50-55 foot-pounds using a calibrated torque wrench. This specification prevents over-tightening which damages the bearing seal and under-tightening which allows axle play. Check torque again after 20 hours of operation. Do not apply thread-locking compound as this makes future removal difficult.
Q: What symptoms indicate the SU 339-A assembly needs replacement?
A: Replace the assembly if you hear squeaking or grinding during operation, detect excessive wheel resistance when rotating by hand, observe flat spots or uneven wear on the wheel tread, or feel the truck pulling to one side. Also replace if the wheel wobbles side-to-side, indicating bearing play. These conditions can cause loss of steering control.
Q: How should the SU 339-A bearing be lubricated and how often?
A: Lubricate the bearing every six months with multipurpose bearing grease. Clean the grease fitting with a cloth before adding fresh grease using a grease gun. Apply grease until it begins to purge from the bearing seal. Limit each grease application to one-quarter ounce. Over-greasing damages seals and allows water and dirt infiltration.
Q: Is the SU 339-A compatible with walkie stacker trucks or only pallet jacks?
A: The SU 339-A assembly works on both pallet jacks and walkie stackers with serial ranges 2010 and later. The 7-inch wheel design and 5500-pound per-wheel rating accommodate both equipment types. Confirm your equipment model in your operations manual matches the 2010-current range before ordering.
Q: What is the expected service life of the SU 339-A assembly under typical warehouse use?
A: Under normal warehouse conditions with proper maintenance, the SU 339-A assembly lasts 20-24 months or approximately 2000-2500 operating hours. Service life decreases significantly on rough concrete, outdoor surfaces, or equipment operated beyond rated load limits. Replace the assembly immediately if bearing failure symptoms appear rather than attempting repair.