Match the part number, measurements and connection points that apply to your trailer.
| Hub Face | Measure hub face to hub face. |
|---|---|
| Spring Center | Measure mounting centers and confirm perch configuration. |
| Capacity | Match the required axle rating. |
| Brakes | Confirm brake type and flange configuration. |
Complete set of four hydraulic brake backing plates for 8,000 lb axle applications. This listing includes two left-hand (driver side) and two right-hand (passenger side) 12-1/4" x 3-3/8" hydraulic brake assemblies.
Designed for forward self-adjusting duo-servo operation and mounting to a standard 4-bolt axle brake flange.
12-1/4" x 3-3/8" hydraulic brakes are commonly used on 8K axle configurations and are not interchangeable with 12-1/4" x 4" heavy-duty systems. Shoe width and backing plate design must match the drum size exactly.
Duo-servo brake assemblies apply braking force in both forward and reverse directions. Self-adjusting mechanisms maintain proper shoe clearance as the linings wear, reducing manual maintenance intervals.
| Specification | Detail |
| Brake Size | 12-1/4" x 3-3/8" |
| Brake Type | Hydraulic Duo-Servo – Self Adjusting |
| Mounting Pattern | 4-Bolt Flange |
| Flange Dimensions | 3-5/8" (Top to Bottom) × 3-7/16" (Left to Right) |
| Axle Capacity Rating | Up to 8,000 lb |
| Dexter Compatibility | 23-402 / 23-403 Series |
| Configuration | 2 Left-Hand & 2 Right-Hand Assemblies |
Verify specifications before installation.
