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Complete 3500# Trailer Brake Kit | 5x4.5 Bolt Pattern | Self-Adjusting (94545-B-FSA-IMP)

$247.00
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At a Glance

  • SKU: 94545-B-FSA-IMP
PRODUCT INFORMATION

Product Details

3500LB AXLE BRAKE CONVERSION

Complete 3500# Trailer Brake Kit | 5x4.5 Bolt Pattern | Self-Adjusting

A comprehensive kit designed to add electric brakes to a single 3500# axle. Features self-adjusting backing plates and 10" drums with a 5-on-4.5" bolt pattern.

Part Number: 94545-B-FSA-IMP 3500# Capacity 5 x 4.5" Bolt Pattern

Overview

This R&P Carriages curated kit provides everything needed to add braking power to a single 3500# trailer axle. Specifically engineered for standard 3500# axle tubes (approx. 2-3/8" OD), this kit includes self-adjusting backing plates which automatically maintain the correct shoe-to-drum clearance, ensuring consistent stopping power and reduced maintenance. It is an ideal aftermarket solution for Spring or Torsion axles, including EZ Lube and standard spindles.

R&P Service Insight

Adding brakes to a single-axle trailer or a second axle on a tandem setup significantly improves towing safety and law compliance.

  • Self-Adjusting: Eliminates the need for manual brake spoon adjustments.
  • Universal Fit: Compatible with Dexter, AL-KO, AXIS, and Quality 3500# axles.
  • All-In-One: Includes bearings, seals, and hardware to prevent mid-job trips to the parts store.

R&P Knowledge Hub

Compatibility: Fits most 3500# axles with a 4-bolt brake flange (2-7/8" center-to-center measurement).

Vehicle / System Fit: Designed for trailers with 5-bolt wheels on a 4.5" diameter bolt circle.

Installation Notes: Your axle must have a square brake flange welded behind the spindle with 4 mounting holes to accept the backing plates.

Performance Insight: 10" x 2.25" brakes provide the standard braking force required for 3500# G.V.W.R. applications.

R&P Repair Insight: Measurement Guide

Before ordering, please verify your axle dimensions to ensure this kit matches your configuration:

  • Axle Tube: Should be approximately 2-1/4" to 2-3/8" OD. (Small 2000# axles are 1-5/8"; Large 5200#+ axles are 2-3/4").
  • Bolt Pattern: 5 x 4.5" is the standard for 3500# axles (measures 4.5" from center of one stud to the back of the third stud).
  • Flange: Verify the 4-hole square plate is present on your axle tube.

Features

Self-Adjusting Design

Brakes automatically adjust to the proper clearance during forward travel, ensuring peak performance.

Complete Hub Assembly

Drums come with bearing races pre-pressed for a faster, cleaner installation process.

EZ Lube Compatible

Includes EZ Lube dust caps, allowing for easy greasing without removing the hub.

Full Hardware Kit

Includes all necessary 7/16" mounting nuts and 1/2-20 lug nuts for the wheels.

Specifications

Specification Detail
Axle Rating 3500 lbs.
Brake Size 10" x 2.25"
Bolt Pattern 5 on 4.5"
Brake Type Electric Self-Adjusting
Flange Pattern 4-Bolt (2-7/8" Spacing)
Stud Size 1/2"-20
Axle Tube Compatibility 2-3/8" OD

Fitment / Application

Category Details
Axle Brands Dexter, AL-KO, AXIS, Quality, Lippert
Axle Types Spring or Torsion
Spindle Style Standard or EZ Lube
Notes Does not fit 2000# axles (1-5/8" tube) or 5200#+ axles (2.75" tube).

Included Components (One Axle Kit)

Quantity Item
2 10" x 2.25" Backing Plates (1 Left, 1 Right) - Self-Adjusting
2 10" Brake Drums (5 on 4.5") with Pressed Races
2 L44649 Outer Bearings
2 L68149 Inner Bearings
2 1.7" 10-19 Grease Seals
2 EZ Lube Dust Caps
10 1/2-20 Matching Lug Nuts
8 7/16" Backing Plate Mounting Nuts
5 on 4.5 Bolt Pattern Measurement Diagram
Final Verification: This is a "Complete Kit" designed for adding brakes to a trailer for the first time. If you are only replacing parts or adding to a second tandem axle, please ensure your axle is equipped with the required 4-bolt mounting flange. Always double-check your wheel bolt pattern (5x4.5") before completing your purchase.
Trailer brake kit, 3500 lb axle brakes, 5x4.5 bolt pattern drum, self-adjusting electric brakes, Dexter compatible brake kit, trailer axle conversion kit.

Related Parts & Kits

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