At a Glance
- SKU: 945475-C-IMP
PRODUCT INFORMATION
Product Details
TRAILER BRAKE CONVERSION / 3.5K AXLE SYSTEM
3,500 lb Trailer Electric Brake Complete Conversion Kit - 5x4.75" GM Bolt Pattern
A comprehensive "bolt-on" solution for 3,500 lb axles originally built without brakes. Includes all essential legal safety components including a breakaway kit and 7-way plug.
Part Number: 945475-C-IMP 3,500 lb Axle Rating 5x4.75" GM Bolt Pattern
Overview
This R&P Carriages Complete Electric Brake Conversion Kit is a high-quality aftermarket solution designed for 3,500 lb trailer axles currently lacking a braking system. Unlike basic kits, the "C-IMP" version provides a full legal safety package to upgrade your landscape trailer or car hauler. The 5x4.75" bolt pattern is specifically intended to match standard GM/Chevy automotive wheels, making it ideal for custom builds or matching tow vehicle spares.
R&P Service Insight
This is the ultimate safety upgrade for utility trailers. By adding brakes, you significantly increase both towing control and the legal hauling capacity of your rig.
- GM Compatibility: Uses the 5x4.75" pattern, common for Chevy/GMC wheels.
- Safety First: Includes the breakaway battery kit required by law in most states for braked trailers.
- Easy Install: Pre-assembled backing plates save significant mechanical labor during installation.
R&P Knowledge Hub
Compatibility: Fits standard 3,500 lb (3.5K) spring or torsion axles equipped with a 4-bolt mounting flange.
Flange Requirements: Your axle must have a square metal plate with 4 holes (2-7/8" center-to-center) welded behind the hub to accept the backing plates.
Installation Notes: Ensure spindles are perfectly clean before installing new bearings and seals. Hand-pack bearings with high-quality wheel bearing grease.
Brake Controller: Electric brakes require an in-cab electric brake controller installed in the tow vehicle to function.
Brand & Fitment Note
Selling Brand: R&P Carriages (Aftermarket Service Kit)
Application Reference: GM, Chevy, and GMC names are used for bolt pattern and wheel compatibility reference only.
What This Means: This is a curated R&P service kit featuring high-quality components designed to meet or exceed trailer industry standards for the specified axle capacity.
Before Ordering: Verify your axle tube diameter and flange presence. This kit will NOT fit 2,000 lb (1-5/8" tube) or 5,200 lb axles.
R&P Installation Insight
Success with a brake conversion depends on proper mounting and maintenance preparation.
- Bearing Pack: Always use a high-quality wheel bearing grease; do not install dry.
- Breakaway Mounting: Mount the breakaway box in a location that is easily accessible but protected from road debris and weather.
- Tire Check: Verify your wheels are 5x4.75"; this is different from the more common trailer 5x4.5" pattern.
Features
Complete Safety Package
Includes a Battery Break-away kit and 7-way plug to ensure your trailer meets highway safety regulations.
GM 5x4.75" Bolt Pattern
Specifically designed for 5 on 4-3/4" hubs, matching common GM automotive wheel specifications.
Pre-Loaded Backing Plates
10" x 2.25" electric brake assemblies come fully assembled for a faster, bolt-on installation.
EZ Lube Compatible
Includes EZ Lube dust caps, making future maintenance and greasing simple and mess-free.
Specifications
| Specification | Detail |
|---|---|
| Part Number | 945475-C-IMP |
| Axle Rating | 3,500 lbs |
| Bolt Pattern | 5 x 4.75" (GM) |
| Brake Size | 10" x 2.25" Electric |
| Inner Bearing | L68149 (1-3/8") |
| Outer Bearing | L44649 (1-1/16") |
| Seal Size | 10-19 (1.719" ID) |
Fitment / Application
| Category | Details |
|---|---|
| Axle Type | Standard 3.5K Spring/Torsion |
| Tube Size | 2-3/8" Diameter Tubes |
| Flange Pattern | Standard 4-Bolt (2-7/8" Center) |
| Wheel Pattern | 5 x 4.75" Bolt Spacing |
| Notes | Will NOT fit 2K or 5.2K axles. Verify flange presence. |
Included Components
| Quantity | Item |
|---|---|
| 2 | 10" Pre-assembled Electric Backing Plates (LH/RH) |
| 2 | 10" Brake Drums (5x4.75" Pattern) with Pressed Races |
| 1 | Full Bearing/Seal Kit (Bearings, Seals, Lugs, EZ Caps) |
| 1 | Complete Battery Break-away Kit (Battery, Case, Switch) |
| 1 | 7-Way Trailer End Plug |
Verify all measurements, specifications, and axle flange presence before installation. This kit is specifically for 3,500 lb axles with a 4-bolt flange and requires an in-cab controller for operation.
Related Parts & Kits
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815-357-3292 · 270 E Jackson St · Seneca, IL 61360
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Found the correct RV keys at a good price with free shipping; the keys worked as expected.
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Needed an unusual axle and leaf-spring size; the team listened and helped him sort out the fit.
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Got the axle he needed right away, set up with a custom spring perch.
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Replacement struts brought a long-used door back to working order.
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