16″ x 4″ Wheels — Hamilton W-1640 Aircraft GSE up to 22,800 lb, 14 Styles

Why is the rubber-on-iron rated higher than the polyurethane?

At 16″ x 4″ size, the wheel construction itself is the capacity constraint — cast iron with a rubber tread reaches 22,800 lb because rubber distributes load more evenly across the contact patch under heavy static loading. Polyurethane on cast iron caps at 9,000 lb at this size due to the bonding adhesive’s tolerance for sustained heavy load — above ~10,000 lb per wheel the bonding agent can fail. For applications above 10,000 lb per wheel, rubber-on-iron or solid forged steel is the spec.

What does “DT70” mean in the Hamilton part number?

DT70 is Hamilton’s polyurethane durometer designation — 70 Shore A durometer (slightly softer than standard polyurethane). The softer compound gives slightly better floor seam compliance at the trade-off of lower peak capacity (4,550 lb vs 9,000 lb for the standard Duralast). Used when the application sees rough surface transitions and the wheel needs to absorb shock without transferring it to the cargo.

What bore size do I need?

Two common bore sizes at 16″ x 4″: 2-7/16″ (the heaviest aircraft tug spec) and 2-3/16″ (alternative bore for some Hamilton yoke assemblies). The 1-1/4″ bore variant (DT70) is the lighter-capacity choice. Pull the existing wheel and measure the bore directly, or reference the yoke OEM part number for bore spec.

What yoke assemblies do these wheels fit?

These wheels are all wheel-only replacements (W-prefix). They fit into existing yoke assemblies typically supplied by Hamilton on aircraft ground support equipment, military trailers, refueler trailers, and similar heavy-equipment OEMs. For a complete caster (yoke + wheel), contact info@casterhq.com with the equipment OEM and model.

Are these mil-spec qualified?

Hamilton supplies these wheels to multiple military OEMs for ground support equipment and trailer applications. Specific mil-spec qualifications depend on the OEM’s equipment-level certification — the wheel itself meets Hamilton’s manufacturing quality standards. For mil-spec documentation, email info@casterhq.com with the application and required spec.