Match the part number, measurements and connection points that apply to your trailer.
| Bearings | Match inner and outer bearing numbers. |
|---|---|
| Seal | Match the seal number or dimensions. |
| Bolt Pattern | Verify the complete lug pattern. |
| Brake Size | Confirm when applicable. |
Part Number: 99865-1PAB-KIT
This hub drum kit is engineered specifically for Rockwell American / Quality 10,000-lb trailer axles using the #99 spindle. It is not a generic 10K assembly. Every component in this kit is dictated by spindle geometry, bearing stack, seal land diameter, and drum depth unique to Rockwell-pattern axles.
Rockwell and Quality 10K axles follow a different design lineage than modern Dexter 10K and 12K running gear. While capacities may appear similar on paper, the physical dimensions are not interchangeable. This kit exists to correctly service trailers built around the #99 spindle standard, which has remained dimensionally consistent for decades.
The #99 spindle defines the entire assembly. If these measurements match your axle, this kit is the correct solution:
| Inner Bearing Journal | 2.00" diameter |
| Outer Bearing Journal | 1.75" diameter |
| Seal Land Diameter | 2.75" |
These dimensions immediately exclude Dexter 10K short spindles, Dexter 12K / 15K spindles, and Lippert LCI 10K variants. If your spindle measures differently, this kit is not compatible.
The bearing pairing in this kit is a long-established Rockwell standard:
| Inner Bearing | 28580 (2.00" ID) |
| Outer Bearing | 25580 (1.75" ID) |
If your axle uses these bearings, the spindle family is confirmed.
The drum supplied in this kit measures 12-1/4" × 3-1/2". This width is critical for heat dissipation under sustained braking loads and is characteristic of Rockwell 10K electric brake systems.
The 4.88" pilot bore places this hub squarely in the Rockwell / Quality 10K family. Smaller pilots indicate lighter assemblies, while larger pilots move into 12K+ designs.
This is an oil bath hub assembly by design — not a grease conversion.
| Seal Size | 2.75" × 3.779" (OB27377 / 91030) |
| Oil Cap Assembly | 3.75" cap with O-ring and plug |
If all four checkpoints match, this kit is not just compatible — it is correct.
