Product Description
Load Wheel Assembly
Frequently Asked Questions
Q: What does SU S339-A include and what is its load rating?
A: SU S339-A is a complete pre-assembled load wheel unit rated for 1800 lbs per wheel. The assembly includes a 1.25 inch hub, sealed bearing, wheel rim, and rubber tire. It is designed for electric pallet jacks and light-duty hand trucks.
Q: Is SU S339-A compatible with trucks that use SU S338-A?
A: No. SU S339-A has a 1.25 inch hub bore while SU S338-A has a 1.5 inch hub bore. The axles are not interchangeable. Installing SU S339-A on a truck designed for SU S338-A will cause the wheel to wobble and the truck will be unsafe to operate.
Q: Can I upgrade from SU S339-A to SU S338-A?
A: No. Upgrading requires replacing the entire axle assembly and steering linkage geometry. The cost of an axle swap is typically 3-4 times the price of simply replacing SU S339-A wheels. If you need higher load capacity, you should purchase a truck designed for SU S338-A from the outset.
Q: What is the bolt pattern for SU S339-A installation?
A: SU S339-A uses four 7/16 inch bolts on a 3 inch bolt circle. Torque must be 45 ft-lbs applied in a star pattern (top, bottom, left, right, then repeat). Verify your truck axle has the correct bolt spacing before ordering.
Q: Is the bearing on SU S339-A sealed or maintenance-free?
A: Yes, the bearing is sealed and maintenance-free. You cannot access the bearing for greasing. If the bearing fails, the entire assembly must be replaced. The sealed bearing is designed to last 3-4 years under normal warehouse use.
Q: How do I troubleshoot if SU S339-A wheels are making noise?
A: A high-pitched squeal indicates a worn bearing seal. A grinding or clicking noise suggests tire damage or a flat spot on the rubber. Lift the truck and spin the wheel by hand. If it does not spin freely or wobbles on the axle, the bearing cartridge is failed and the assembly must be replaced.