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 two genuine Dexter 12-1/4" x 3-3/8" electric brake backing plate assemblies designed for 9,000–10,000 lb trailer axle applications. This listing includes both the left-hand (driver side) and right-hand (passenger side) assemblies.
Each brake assembly features a forward self-adjusting mechanism and comes fully pre-assembled on the backing plate for efficient installation.
This set provides enough assemblies to service one complete axle (two wheels).
Electric brake assemblies operate through a brake controller that energizes the magnet inside the drum, expanding the brake shoes outward to create braking force.
The Forward Self-Adjusting (FSA) system automatically maintains proper shoe-to-drum clearance as lining wear occurs. When enough gap develops, the adjuster mechanism advances the screw assembly at the bottom of the brake, helping maintain consistent braking performance.
12-1/4" x 3-3/8" brake assemblies are commonly used on 9K–10K trailer axles. Always verify brake size, axle capacity, mounting pattern (7 bolt), and proper left/right orientation before installation.
| Specification | Detail |
| Manufacturer | Dexter |
| Brake Diameter | 12-1/4 Inches |
| Brake Width | 3-3/8 Inches |
| Axle Rating | 9,000–10,000 lbs (per pair) |
| Mounting Pattern | 7 Bolt Flange |
| Brake Type | Electric Drum Brake |
| Adjustment | Forward Self-Adjusting |
| Configuration | Left & Right Pair |
Verify specifications before installation.
