SU S258

Frequently Asked Questions

Q: What is the difference between the SU S258 (95A) and SU S258-EZ (85A) load wheels?
A: The SU S258 features a 95A Shore A polyurethane tread, which is harder and more load-rated for heavy-duty applications with hard floor surfaces. The SU S258-EZ is a softer 85A formulation designed for gentle floors like wood or epoxy where reduced impact and noise are required. Do not interchange them; 95A on soft floors causes excessive wear, and 85A under heavy loads leads to permanent deformation.

Q: Is the SU S258 compatible with non-electric lift trucks?
A: The SU S258 is designed for electric lift truck load wheel replacements. While the mechanical design may fit some manual or gasoline-powered lift trucks, compatibility is not guaranteed. Verify axle diameter, bearing bore, and mounting geometry. Use only wheels specified in your truck maintenance manual to ensure proper load distribution and braking performance.

Q: Can I replace just one wheel or must I replace the complete set?
A: Always replace wheels in sets of four or all load wheels on the same axle. Mixing wheel hardness or wear levels causes uneven load distribution, binding, and accelerated failure on the remaining wheels. Even slight wear differences between front and rear wheels will create operational problems within 100 operating hours.

Q: What environmental factors affect SU S258 performance and durability?
A: The polyurethane tread hardens in cold temperatures below 40 degrees F and becomes tacky in heat above 95 degrees F. Humidity causes the white polypropylene hub to swell slightly. Prolonged exposure to oils, solvents, or corrosive chemicals can degrade the polyurethane. Store wheels indoors and away from direct sunlight. Do not operate in chemical processing or cold storage environments without consulting compatibility data.

Q: How do I diagnose if my SU S258 wheels need replacement?
A: Symptoms include visible flat spots, chunking, or tread separation on the red polyurethane. Listen for bearing noise or grinding. The truck may pull to one side if wheels are unevenly worn. Check wheel runout with a dial indicator; if lateral runout exceeds 0.150 inch, the wheel is no longer serviceable. Remove and inspect the Delrin bearing for pitting or discoloration.

Q: What is the expected service life of the SU S258 under typical warehouse conditions?
A: Under normal indoor warehouse duty with clean concrete floors, the SU S258 (95A) typically lasts 3 to 4 years with regular use. High-volume operations or rough floors reduce lifespan to 18 to 24 months. Proper truck alignment, daily cleaning, and monthly bearing lubrication extend service life. Replace immediately if bearing develops play, as continued operation will damage the polypropylene hub.