Description
The SOUTHWEST WHEEL® Round R104BT8X BT8 Spindle, 4-4″ Bolt Circle Trailer Hub, & 8″ x 3.75″ White Trailer Wheel Combo (Part R1BT8BT121E-40844) is a complete ready-to-install wheel end assembly. This convenient combo includes a BT8 spindle, matching 4 on 4″ hub with bearings, and a durable 8″ white wheel — perfect for small utility trailers, boat trailers, and other light-duty applications.
Key Features
- Part Number: R1BT8BT121E-40844
- Spindle: Round R104BT8X BT8 Spindle (1″ Journals)
- Spindle Dimensions: Base 1-1/4″ × Length 3-3/8″ × Overall 8-1/4″
- Hub: 4 on 4″ Bolt Circle (L44643 Inner & Outer Bearings)
- Wheel: 8″ x 3.75″ White Steel Trailer Wheel
- Wheel Center Bore: 2.75″
- Capacity: 1,000 lbs. (per pair)
- Includes: Pre-raced hub with bearings, seal, grease cap, lug nuts, and spindle
- Brand: SOUTHWEST WHEEL®
This all-in-one combo package is designed for easy assembly and reliable performance on small single-axle trailers. The complete kit saves time and ensures all components are properly matched for smooth, safe operation.
Questions about this wheel, hub, and spindle combo? Call our trailer experts at 1-800-866-3336.
Browse more Hubs & Spindles.
| Part No | Quantity | Description |
| X1023R | 4 | Nut, Cone 60-Deg |
| RVI-BT-4400 | 1 | Hub, 2K, 440, Cupped & Studded |
| GS-1250DLR | 1 | Seal, Grease 1.25 ID |
| DC-200 | 1 | Grease Cap |
| L-44643 | 2 | Bearing Cone (L44643) |
| R104BT8 | 1 | 1.25″ Round BT8 Spindle |
| FS-SN100 | 1 | 1″ Spindle Nut |
| FA-SW100 | 1 | 1″ Spindle Washer |
| 18X134CP | 1 | Cotter Pin |
| 40844 | 1 | 4.80-8 LoadStar 4-4″ Wheel and Tire |
