Product Description
The SU S684-XL Idler Caster is designed for electric lift trucks, providing reliable performance and durability. This high-quality caster features a Polyurethane XL 97A tread and precision hub construction, making it ideal for aftermarket and replacement parts applications.
Specifications: 8.000 inch diameter x 4.000 inch width (8.000" x 4.000" | 8 x 4 wheel | 8 x 4 | 203.20mm x 101.60mm)
• Polyurethane XL 97A tread for enhanced grip and longevity
• Precision hub construction for improved stability
• Suitable for electric lift truck assemblies
This idler caster is specifically engineered to meet the demands of electric lift trucks, ensuring optimal performance in various applications.
Specifications
Material & Construction
| Caster Tread Hardness | 97A shore durometer |
| Caster Material | Polyurethane XL formulation |
Part Numbers
| Manufacturer Part Number | SU S684-XL |
| OEM Part Number | SU S684-XL |
| Cross-Reference Part Numbers | SU S684-XL-A; No additional cross-reference part numbers available |
Wheel Dimensions
| Outside Diameter | 8 |
| Inside Diameter | 2.25 |
| Width Side to Side | 4 |
| Bore Depth | 0.63 |
| Bore Outside Diameter | 2.4404 |
Frequently Asked Questions
Q: Is the SU S684-XL equivalent to the SU S684-XL-A?
A: No. The SU S684-XL is the idler wheel tread only, while the SU S684-XL-A includes the complete assembly with sealed clutch bearings and hub. If you need just the replacement tread, order the SU S684-XL. If you need the full bearing cartridge assembly, order the SU S684-XL-A. Both have identical 8x4 dimensions and 97A durometer polyurethane.
Q: What electric lift truck models use the SU S684-XL caster?
A: The SU S684-XL is a universal fit 8 inch by 4 inch idler wheel designed for most electric lift trucks and pallet jacks that call for an 8x4 configuration with a 30mm bearing bore. Verify your truck manual or existing wheel diameter and width before ordering. The 2.25 inch inside bore and 30mm bearing ID must match your existing hub assembly.
Q: Can I replace the SU S684-XL tread without removing the entire wheel hub?
A: Yes. The SU S684-XL is a direct tread replacement. Press or tap the worn tread off the hub core and press the new SU S684-XL tread onto the same hub. Use a bearing puller or press tool to avoid damaging the hub bore. Do not attempt to remove the axle unless the hub bore is damaged.
Q: What is the load rating and durability expectation for the SU S684-XL?
A: The SU S684-XL polyurethane XL 97A tread is rated for continuous duty in indoor electric lift truck use. Expected service life is 1,500 to 3,000 operating hours depending on load, floor surface, and duty cycle. The 97A shore durometer provides excellent wear resistance on concrete and smooth floors. Softer floors or rough surfaces reduce tread life.
Q: Does the SU S684-XL work in outdoor or wet environments?
A: Not recommended. The polyurethane XL 97A tread is formulated for dry indoor use only. Exposure to water, UV, or extreme temperatures degrades the tread bond and reduces grip. If your truck operates outdoors, consult the manufacturer for suitable alternatives. Do not use the SU S684-XL on damp concrete or wet surfaces.
Q: How do I check if the SU S684-XL tread is worn out?
A: Signs of wear include visible flat spots, cracks, crumbling edges, or separation from the hub core. If tread thickness drops below 0.5 inches or the wheel tilts when rolling, replace it. Listen for squeaking or grinding noise during operation, which indicates hub bearing damage or hub bore wear. If the hub bore is damaged, replace the full SU S684-XL-A assembly instead of the tread alone.