SU S448-XL-A

Frequently Asked Questions

Q: Does the SU S448-XL-A come pre-assembled with bearings and is installation plug-and-play or do I need to perform modifications?
A: The SU S448-XL-A is described as a pre-assembled wheel assembly with bearing included. Installation requires removing the old wheel from the axle and pressing or installing the new assembly in its place. If your truck uses snap rings or retaining clips, these may transfer from the old wheel. Verify bearing type and sealed rating against your axle specification; if bearings do not match existing ones, you may need to also replace axle seals or spacers. Consult your truck manual for assembly-specific installation steps.

Q: The spec sheet says SU S448-XL-A supersedes SU 448-XL. Are these dimensions identical and can I use the A version as a direct replacement?
A: Yes. The SU S448-XL-A is a direct replacement for SU 448-XL. Both share the same mounting bore diameter and width. The A version improves upon the original by including a pre-assembled bearing, potentially upgraded polyurethane bonding technology (XL3 if compatible with Superior Tire XL series), and higher durability tread. You can install the A version into any truck currently running the base SU 448-XL without modifications, provided all retaining hardware transfers or is compatible.

Q: What is the polyurethane bonding technology used in the SU S448-XL-A and does it perform better than standard bonding?
A: The SU S448-XL-A uses polyurethane-to-steel bonding and may employ XL3 bonding technology if matching Superior Tire XL series specifications. XL3 technology improves adhesion and reduces delamination risk compared to standard mechanical bonding. If your wheel is listed as XL series compatible, you are receiving enhanced durability. To confirm if your assembly uses XL3 bonding, verify the product label or contact Superior directly with your purchase order number.

Q: How do I verify that the SU S448-XL-A bearing is properly seated and maintaining correct alignment after installation?
A: After installation, rotate the wheel by hand; it should spin freely without binding or grinding noise. If the wheel is difficult to rotate or makes clicking sounds, the bearing may not be fully seated or may be damaged. Spin the wheel under light load for 5 to 10 minutes; excessive heat development indicates friction from improper seating. Use an infrared thermometer to check bearing temperature; normal operating temperature is 40 to 60 degrees Celsius. If temperature exceeds 70 degrees Celsius, stop operation and reinstall or replace the bearing.

Q: What maintenance is required for the SU S448-XL-A bearing and tread to extend wheel life?
A: Clean the polyurethane tread monthly with water and a soft brush to remove dirt and debris. Do not apply bearing grease unless your bearing is open (non-sealed); sealed bearings are maintenance-free and over-greasing causes pressure buildup leading to seal failure. Inspect the wheel quarterly for signs of bonding failure, flat spots, or tread cracks. If you notice wobbling or radial runout exceeding 0.25 inches, check bearing installation and retaining hardware. Sealed bearings typically last the life of the wheel and require replacement only if noise or binding develops.

Q: If the SU S448-XL-A bearing fails, can I replace only the bearing or must I buy a complete new wheel assembly?
A: If the bearing fails while the tread remains in good condition (more than 50 percent tread depth), you can attempt bearing replacement. Remove the wheel from the axle using a bearing puller to extract the failed bearing, then press a new sealed bearing matching the bore diameter and load rating onto the axle. Ensure the new bearing fits the existing bore race diameter. This approach saves money but requires access to a bearing press. If tread is worn or bonding is compromised, replace the entire assembly for safety and to avoid repeated failures.