Product Description
SU S684-XL-A is an 8 inch by 4 inch EZ compound idler caster wheel assembly, specifically engineered for continuous duty use in electric lift truck applications. This durable wheel features sealed clutch bearings and a polyurethane tread, ensuring reliable performance under demanding conditions.
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) | Bearing ID: 30mm (1.181 inch bore | 30.000mm ID)
• Constructed with a corrosion-resistant steel core
• Equipped with nitrile radial seals for enhanced durability
• Designed for smooth operation and reduced wear
This caster wheel assembly is ideal for electric lift trucks, providing excellent support and mobility in various industrial settings.
Specifications
Material
| Tread Compound | Polyurethane, Shore 97A hardness |
Part Numbers
| Manufacturer Part Number | SU S684-XL-A |
| OEM Part Number | SU S684-XL-A |
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: What is included in the SU S684-XL-A assembly?
A: The SU S684-XL-A is a complete idler caster assembly that includes the 8x4 polyurethane wheel tread, precision hub core, and sealed clutch bearings pre-installed. The bearing bore is 30mm (1.181 inch). This is a ready-to-install unit requiring only mounting bolts to the truck frame or carriage.
Q: Is the SU S684-XL-A plug-and-play or does it require modification?
A: The SU S684-XL-A is plug-and-play if your truck uses a 30mm axle and 8x4 wheel spacing. Remove the old assembly by unbolting it from the frame. Bolt the SU S684-XL-A in place using the same mounting holes. No machining, pressing, or bearing replacement is needed. If your truck uses a different axle diameter, the SU S684-XL-A will not fit.
Q: How do sealed clutch bearings work in the SU S684-XL-A?
A: The sealed clutch bearings allow the wheel to spin freely when the truck moves forward and lock automatically when the truck brakes or moves backward. This prevents wheel scuffing and damage from lateral forces. The seals protect bearings from dust and contaminants. Do not attempt to disassemble or repack bearings. If bearings seize or rattle, the entire SU S684-XL-A assembly must be replaced.
Q: Can I use the SU S684-XL-A on a different axle size?
A: No. The SU S684-XL-A is designed for a 30mm bearing bore only. If your truck axle is 25mm, 35mm, or 40mm, the assembly will not mount or will bind. Do not force-fit. Verify your existing axle diameter before ordering. If you need a different size, contact your supplier for the correct cross-reference part number.
Q: What maintenance is required for the SU S684-XL-A?
A: The SU S684-XL-A sealed bearings require no lubrication or repacking. Inspect monthly for noise, flat spots, or cracks in the tread. If the wheel tilts or wobbles, check that all mounting bolts are tight. Do not pressure wash the bearings. Expected service life is 2,000 to 4,000 hours. Replace the entire assembly when tread wear exceeds 0.5 inches or bearing failure occurs.
Q: What is the weight and load capacity of the SU S684-XL-A?
A: The SU S684-XL-A supports up to 1,200 to 1,500 pounds per wheel on a four-wheel truck, depending on truck design and load distribution. Total truck capacity is typically 3,000 to 6,000 pounds. Exceeding load limits causes tread deformation, bearing failure, and loss of steer control. Always verify your truck rated capacity in the operator manual.