Product Description
Load Wheel Assembly
Frequently Asked Questions
Q: What is the difference between SU S663-XL and SU S663-XL-A?
A: SU S663-XL is the wheel component. SU S663-XL-A is the complete assembly that includes the wheel, bearing, and hub assembly. The -A variant is ready to install as a single unit. Use SU S663-XL-A when replacing the entire wheel assembly, or use SU S663-XL when replacing only the tire portion on an existing hub.
Q: Is SU S663-XL-A a direct replacement for my trucks original wheel assembly?
A: SU S663-XL-A is a direct replacement only if your truck originally shipped with an XL extended-duty configuration. Verify your truck model and look for XL designation in the nameplate or documentation. Installing SU S663-XL-A on a truck specified for standard wheels may cause steering problems or suspension damage.
Q: How do I install the SU S663-XL-A load wheel assembly?
A: Lift the truck on a jack stand, remove the retaining clip or axle nut, and use a wheel puller to remove the old assembly. Slide the SU S663-XL-A onto the axle shaft, align the bore, and secure with the retaining clip or nut. Torque to manufacturer specification, typically 40 to 60 foot-pounds depending on shaft diameter. Test the wheel rotation and steering before lowering.
Q: Does the SU S663-XL-A come with bearing pre-loaded or do I need to lubricate it before use?
A: SU S663-XL-A assemblies are pre-greased at the factory and ready for installation. Do not add additional grease before mounting unless your maintenance manual specifies additional application. After installation, establish a re-lubrication schedule per your truck manual, typically every 500 to 1000 hours or annually, whichever comes first.
Q: What symptoms indicate the SU S663-XL-A bearing has failed?
A: A grinding or clicking noise when the truck moves indicates bearing damage. Excessive play or wobble when you grab the wheel at the 3 and 9 o clock positions suggests bearing wear. Leaking grease or overheating at the hub also signals failure. Remove the wheel immediately and replace the entire SU S663-XL-A assembly if any of these symptoms occur.