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12-1/4" x 4" Electric Trailer Backing Plate – 10K HD – Left Hand – 7 Bolt (BK-10HDE-01)

$135.42
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At a Glance

  • SKU: BK-10HDE-01
PRODUCT INFORMATION

Product Details


Electric Trailer Brake Assembly

12-1/4" x 4" Electric Trailer Backing Plate – 10K HD – Left Hand – 7 Bolt

Heavy-duty left-hand electric trailer brake assembly for 12-1/4" x 4" drum brake applications on 10,000 lb heavy-duty axle setups. Designed for 7-bolt mounting flanges and Dexter-style 10K HD applications where measurements and mounting pattern match.

Part Number: BK-10HDE-01 12-1/4" x 4" Brake Size Left / Driver Side

Key Measurements & Specs

Specification Detail
Part Number / SKU BK-10HDE-01
Product Type Electric trailer brake assembly / backing plate assembly
Brake Size 12-1/4" x 4"
Axle Application 10,000 lb heavy-duty trailer axle applications
Mounting Pattern 7-bolt brake flange
Quantity Included 1 left-hand brake assembly

Fitment / Application

Category Details
Trailer System Electric drum brake trailer axle system
Primary Fit 12-1/4" x 4" 10K HD electric brake applications with 7-bolt flange
Orientation Left hand / driver side only
Fitment Method Verify brake size, axle rating, mounting flange pattern, drum compatibility, and left/right orientation before ordering.
Application Note Dexter-style reference is for fitment guidance only. Confirm existing brake specifications before installation.

Top Features

Feature Buyer Benefit
Self-Adjusting Design Forward self-adjusting setup helps maintain brake adjustment during normal service use.
10K HD Application Built for heavy-duty 10,000 lb trailer axle brake applications where the original setup matches.
7-Bolt Mounting Matches 7-bolt brake mounting flanges used on compatible heavy-duty axle assemblies.
Left-Side Replacement Useful when replacing only the driver-side brake assembly or matching with the right side for axle service.

Overview

BK-10HDE-01 is a left-hand electric trailer brake assembly for 12-1/4" x 4" 10K heavy-duty drum brake applications. It is configured for 7-bolt brake mounting flanges and is intended for compatible Dexter-style 10K HD axle setups where the brake size, flange pattern, and orientation match the trailer being serviced.

R&P Service Insight

Heavy-duty brake assemblies should be matched by measurement and side orientation, not by axle rating alone. Before ordering, compare the existing brake assembly against the size, mounting pattern, and left/right layout listed here.

  • Brake Size: Confirm the drum brake size is 12-1/4" x 4".
  • Mounting Flange: Confirm the axle uses a 7-bolt brake flange.
  • Side Orientation: This listing is for the left / driver side brake assembly only.

R&P Knowledge Hub

Compatibility: Designed for compatible 10K heavy-duty electric drum brake applications using a 12-1/4" x 4" brake size and 7-bolt mounting flange.

Vehicle / System Fit: Trailer axle electric brake systems on matching 10,000 lb HD axle setups.

Installation Notes: Verify the existing brake flange, drum size, magnet wiring, and left/right brake orientation before installation. Mounting hardware is not listed as included.

Performance Insight: Self-adjusting brake assemblies are commonly used to help maintain brake shoe adjustment under normal service conditions, reducing the need for manual adjustment when installed and functioning correctly.

Brand & Fitment Note

Selling Brand: R&P Carriages / listed aftermarket trailer brake assembly.

Application Reference: Dexter-style and 10K HD references describe compatible application style only where measurements and mounting points match.

What This Means: This listing is for one left-hand electric trailer brake assembly, not a guaranteed OEM-branded item unless separately stated and verified on the product packaging or invoice.

Before Ordering: Verify brake size, mounting pattern, axle rating, drum compatibility, left/right orientation, and included components before installation.

R&P Repair Insight

When servicing heavy-duty electric brakes, it is often best to inspect both sides of the axle. Uneven wear, weak magnet pull, damaged wiring, contaminated shoes, or an incorrect left/right replacement can affect braking performance.

  • Left vs. Right: This is the left / driver side assembly. Pair it with the matching right side when servicing both ends of the axle.
  • Drum Match: Confirm the brake drum is compatible with 12-1/4" x 4" shoes before installation.
  • Electrical Check: Inspect wiring, grounds, brake controller output, and magnet connections during replacement.

Features

12-1/4" x 4" Brake Size

Configured for heavy-duty electric drum brake applications using a 12-1/4" diameter by 4" wide brake setup.

10K Heavy-Duty Application

Built for compatible 10,000 lb heavy-duty trailer axle brake systems where the axle and drum specifications match.

7-Bolt Mounting Pattern

Designed for 7-bolt brake mounting flanges commonly used in compatible heavy-duty trailer axle applications.

Forward Self-Adjusting

Self-adjusting electric brake design helps maintain proper brake adjustment during normal trailer service use.

Left-Hand Assembly

This listing is for the left / driver side brake assembly only. Confirm side orientation before ordering.

Dexter-Style Fitment Reference

Compatible with listed Dexter-style 10K HD applications where brake size, mounting pattern, and assembly layout match.

Included Components

Quantity Item
1 Left-hand 12-1/4" x 4" electric brake assembly / backing plate assembly
Not Included Right-hand brake assembly, pair set, drums, bearings, seals, mounting hardware, and additional axle service components unless separately shown or stated.
Important Fitment Note: This listing is for the LEFT / driver side brake assembly only. Verify all measurements, brake size, axle rating, 7-bolt mounting flange, drum compatibility, left/right orientation, wiring condition, and included components before installation. Dexter-style references describe application fitment only unless OEM status is specifically stated and verified.
BK-10HDE-01 12-1/4 x 4 electric brake assembly left 10K HD trailer brake backing plate left hand driver side 7 bolt electric trailer brake self adjusting FSA 10000 lb heavy duty axle Dexter style 10K HD brake assembly replacement trailer brake parts R&P Carriages

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BEHIND THIS LISTING
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DIGITAL PRESENTATION & DEVELOPMENT Ken Martin Ken’s handwritten signature
ONLINE SALES & QUALITY ASSURANCE Rayn Fisher
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