3500 lb Single Axle Kit Idler 89/74 – Master Kit (612SD & 614SD)
SKU # 35SAD8974545MK
Build a complete 6′ wide single axle utility trailer with this comprehensive 3,500 lb Master Kit. Designed around an 89″ hub face / 74″ spring center idler axle, this package includes the trailer blueprints, axle and suspension, tires and wheels, fenders, coupler, jack, lighting, wiring, gate hardware, tie-down points, safety chains, and additional fabrication components.
This SD Master Kit also includes a transition plate, making it a more complete package for the applicable 6′ x 12′ and 6′ x 14′ single axle dovetail-style trailer builds.
What’s Included
Blueprints
- (1) Utility Trailer 6′ x 12′ Single Axle Flat / Dove Tail Blueprint Package
Axle & Suspension
- (1) 3,500 lb Idler Axle – 89″ Hub Face / 74″ Spring Center
- Double Eye Leaf Springs
- U-Bolt Mounting Hardware
- (1) Single Axle Hanger Kit
Tires, Wheels & Fenders
- (2) ST205/75R15 Trailer Tires & Wheels – 5 Lug
- (10) Lug Nuts
- (2) Smooth Rolled Single Axle Fenders
- (2) Single Fender Backs
Coupler, Jack & Safety Equipment
- (1) 2″ Trailer Coupler
- (1) 5,000 lb Trailer Jack
- (1) Jack Foot Plate
- (2) 5/16″ x 30″ Grade 70 Safety Chains with 7,600 lb S-Hooks
- (2) Chain Loops
Frame & Fabrication Components
- (1) Transition Plate
- (1) Cover Plate
- (2) Indicator Tabs
Trailer Wiring & Lighting
- (1) 25′ 4-Way Flat Trailer Wiring Harness
- (1) 12V LED Left / Right Tail Light Set
- (1) 3-Light LED Identification Light Bar
- (2) 3/4″ Amber LED Side Marker Lights
- (1) License Plate Bracket
- (2) Light Brackets
Gate & Latch Hardware
- (6) Inner Gate Hinges
- (2) Outer Gate Hinges
- (2) Tailgate Latches – Left & Right
- (2) U-Latches
Cargo & Visibility Components
- (4) Tie-Down Rings
- (4) 2″ x 12″ Conspicuity Tape Strips
- (2) 1″ x 12″ Conspicuity Tape Strips
Kit Specifications
| Specification | Details |
|---|---|
| SKU | 35SAD8974545MK |
| Trailer Size | 6′ x 12′ / 6′ x 14′ Single Axle |
| Trailer Style | Straight / Dove Tail Compatible |
| Axle Capacity | 3,500 lbs |
| Axle Type | Idler / Non-Braking |
| Hub Face | 89″ |
| Spring Center | 74″ |
| Tire Size | ST205/75R15 |
| Wheel Pattern | 5 Lug |
| Configuration | Single Axle |
| Coupler Size | 2″ |
| Jack Capacity | 5,000 lbs |
| Wiring Connection | 4-Way Flat |
| Kit Type | Complete Master Kit |
Features & Benefits
Complete Single Axle Trailer Build Package
This Master Kit combines the major mechanical, electrical, safety, and body components needed for a 6-foot-wide single axle utility trailer build.
3,500 lb 89/74 Idler Axle
The included 89-inch hub face / 74-inch spring center idler axle provides a dependable foundation for medium-duty single axle utility trailer applications.
ST205/75R15 Tire & Wheel Assemblies
Two ST205/75R15 5-lug trailer tire and wheel assemblies are included along with the required lug nuts, providing a ready-to-install wheel package.
Complete Suspension System
The axle, leaf springs, U-bolt hardware, and single axle hanger kit are matched together to simplify installation and fabrication.
Transition Plate Included
The included transition plate adds an important fabrication component for dovetail-style trailer configurations and helps distinguish this SD Master Kit from the standard straight-deck package.
Smooth Rolled Steel Fenders
A pair of smooth rolled single axle fenders and matching fender backs provide proper tire coverage while giving the completed trailer a clean appearance.
Complete LED Lighting Package
LED tail lights, amber side markers, a three-light identification bar, 25-foot 4-way flat harness, light brackets, and license plate bracket provide the primary electrical and lighting components needed for the build.
Gate & Latch Hardware
Six inner gate hinges, two outer gate hinges, left and right tailgate latches, U-latches, and indicator tabs provide the primary hardware needed to fabricate and secure the trailer gate.
Tie-Down & Safety Components
Four tie-down rings provide cargo securement points, while Grade 70 safety chains, chain loops, and reflective conspicuity tape add important towing and visibility components.
Trailer Tongue Components
The included 2-inch coupler, 5,000 lb jack, jack foot plate, transition plate, and cover plate provide essential components for completing the front and transition areas of the trailer.
Common Applications
- 6′ x 12′ Utility Trailers
- 6′ x 14′ Utility Trailers
- Dove Tail Utility Trailers
- Flat Deck Utility Trailers
- Lawn & Landscape Trailers
- ATV & UTV Trailers
- Motorcycle Trailers
- Small Equipment Trailers
- Farm & Property Trailers
- General-Purpose Cargo Trailers
- DIY Trailer Builds
- Custom Trailer Fabrication
Why Choose a Master Kit?
Building a trailer from scratch means sourcing dozens of individual components that all need to work together. This Master Kit simplifies the process by combining the blueprints, axle, suspension, tires, wheels, fenders, towing hardware, electrical system, gate hardware, transition components, safety equipment, and tie-down points into one convenient package.
That means fewer individual parts to track down and a much clearer path from raw material to a finished trailer.
Important Fitment & Build Information
Please verify all measurements, capacities, and component requirements before beginning your trailer build.
- Hub Face: 89″
- Spring Center: 74″
- Axle Capacity: 3,500 lbs
- Axle Type: Idler / Non-Braking
- Tire Size: ST205/75R15
- Coupler Size: 2″
- Wiring: 4-Way Flat
- Transition Plate: Included
The 3,500 lb axle rating does not automatically mean the completed trailer is rated for 3,500 lbs of payload. Final trailer capacity and legal GVWR depend on the completed trailer design and the lowest-rated component in the assembly, including the frame, axle, suspension, tires, wheels, coupler, and other hardware.
Need help with your build or selecting the correct trailer kit? Contact Highway 96 Trailers and our team can help you choose the right setup for your project.








