12-1/4" x 4" Electric Trailer Backing Plate – 10K HD – Right Hand – 7 Bolt
Heavy duty right-hand electric trailer brake assembly for 12-1/4" x 4" 10,000 lb HD drum brake applications using a 7-bolt brake mounting flange.
Key Measurements & Specs
| Specification | Detail |
|---|---|
| Part Number / SKU | BK-10HDE-02 |
| Selling Brand | R&P Carriages / aftermarket replacement |
| Product Type | Electric trailer brake assembly / backing plate |
| Brake Size | 12-1/4" x 4" |
| Axle Application | 10,000 lb heavy duty trailer axle applications |
| Quantity Included | 1 right-hand brake assembly |
Fitment / Application
| Category | Details |
|---|---|
| Trailer System | Electric drum brake system |
| Primary Fit | 12-1/4" x 4" 10K HD brake applications with 7-bolt mounting |
| Orientation | Right hand / passenger side only |
| Fitment Method | Verify brake size, axle rating, drum width, 7-bolt flange pattern, and right-side orientation before ordering. |
| Important Note | Dexter-style references describe application fitment only. This listing is not claiming genuine Dexter OEM branding unless separately stated by the product label or packaging. |
Top Features
| Feature | Buyer Benefit |
|---|---|
| Self-Adjusting Design | Helps maintain proper shoe adjustment during normal brake service intervals. |
| 10K HD Application | Built for heavy duty 10,000 lb trailer axle brake setups where the 12-1/4" x 4" size is required. |
| 7-Bolt Mounting | Matches compatible 7-bolt brake mounting flanges used on heavy duty trailer axles. |
| Right-Side Assembly | Correct replacement when the passenger-side brake assembly is worn, damaged, weak, or contaminated. |
Overview
The BK-10HDE-02 is a right-hand electric trailer brake assembly for heavy duty 10,000 lb axle applications using a 12-1/4" x 4" brake size and 7-bolt mounting flange. It is intended for compatible 10K HD drum brake setups where the existing brake size, mounting pattern, and side orientation match this listing.
R&P Service Insight
Heavy duty brake assemblies should be matched by measurement and orientation, not by axle rating alone. Many 9K, 10K general duty, and 10K heavy duty brake setups can look similar but use different shoe widths and mounting configurations.
- Measure the Brake: Confirm 12-1/4" drum diameter and 4" shoe width.
- Check the Flange: Confirm the axle has the correct 7-bolt brake mounting pattern.
- Match the Side: This listing is for the right / passenger side only.
R&P Knowledge Hub
Compatibility: Designed for compatible 12-1/4" x 4" 10K HD electric trailer brake applications with a 7-bolt flange. Verify before ordering.
Vehicle / System Fit: Trailer electric drum brake systems used on heavy duty 10,000 lb axle applications.
Installation Notes: Inspect the brake drum, wiring, magnet wear surface, bearings, seals, and mounting hardware during brake service. Replace damaged or worn companion parts as needed.
Performance Insight: The 12-1/4" x 4" brake size is specific to heavy duty drum brake applications; using the wrong width or mounting pattern can prevent proper installation and braking performance.
Brand & Fitment Note
Selling Brand: R&P Carriages / aftermarket replacement brake assembly.
Application Reference: Dexter-style and 10K HD references are used to describe common application fitment where brake size, flange pattern, axle configuration, and orientation match.
What This Means: This listing is for an aftermarket right-hand electric trailer brake assembly, not a guaranteed OEM-branded item unless specifically stated and verified on the product packaging.
Before Ordering: Verify brake size, axle rating, drum width, mounting bolt pattern, right/left orientation, electrical condition, and included components before installation.
R&P Repair Insight
When replacing one heavy duty brake assembly, inspect the opposite side and confirm both brakes on the axle are adjusted and functioning evenly. Uneven braking can come from worn shoes, weak magnets, contaminated linings, wiring problems, or mismatched components.
- Confirm Orientation: Right-hand and left-hand assemblies are not interchangeable.
- Inspect the Drum: A worn, scored, cracked, or contaminated drum can reduce braking performance even with a new backing plate.
- Service the Axle End: Check bearings, seals, grease condition, and spindle condition while the drum is removed.
Features
Right-Hand Brake Assembly
Passenger-side assembly for compatible 10K HD trailer brake applications using the correct right-side orientation.
12-1/4" x 4" Brake Size
Matches heavy duty drum brake applications requiring a 12-1/4" diameter by 4" wide brake assembly.
7-Bolt Mounting Pattern
Designed for compatible heavy duty axle brake flanges using a 7-bolt mounting configuration.
Self-Adjusting Electric Brake
Forward self-adjusting electric brake design helps maintain shoe adjustment during normal trailer operation and service intervals.
Included Components
| Quantity | Item |
|---|---|
| 1 | Right-hand 12-1/4" x 4" electric trailer brake assembly / backing plate |
| Not Included | Mounting hardware, brake drum, bearings, seals, grease cap, wiring connectors, and left-side brake assembly unless separately purchased |
Related Options
Need the matching side or a complete axle-end refresh? Choose the correct option below before checkout.
