3500 lb Tandem Axle Kit (7K Capacity) 89/74 – Foundation Kit

SKU # 35TA8974545FK

Start your tandem axle trailer build with the core running gear using this 7,000 lb Tandem Axle Foundation Kit. Built around two 3,500 lb axles with an 89″ hub face / 74″ spring center, this package includes one idler axle, one electric brake axle, the required springs and U-bolt mounting hardware, and a tandem axle hanger kit.

This Foundation Kit is ideal for builders who already have their tires, wheels, fenders, coupler, jack, lighting, wiring, and other trailer components—or who want the flexibility to select those items separately.

What’s Included

Axles & Suspension

• (1) 3,500 lb Idler Axle – 89″ Hub Face / 74″ Spring Center
• (1) 3,500 lb Electric Brake Axle – 89″ Hub Face / 74″ Spring Center
• Double Eye Leaf Springs
• U-Bolt Mounting Hardware
• (1) Tandem Axle Hanger Kit

Kit Specifications

Features & Benefits

Essential Tandem Axle Foundation

This kit provides the primary axle and suspension components needed to establish the running gear foundation of a tandem axle trailer.

7,000 lb Combined Axle Capacity

Two 3,500 lb axles provide a combined axle capacity of 7,000 lbs, making this package a strong starting point for utility, landscape, equipment, and custom tandem axle trailer builds.

Idler & Electric Brake Axle Combination

The kit includes one idler axle and one electric brake axle, giving your trailer braking capability while maintaining a straightforward tandem axle configuration.

89/74 Axle Configuration

Both axles feature an 89-inch hub face and 74-inch spring center, making critical fitment measurements easy to verify before installation.

Complete Tandem Suspension Components

Leaf springs, U-bolt mounting hardware, and the tandem axle hanger kit are included to support and mount both axles as a complete suspension system.

Flexible Build Option

A Foundation Kit allows you to select your own tires, wheels, fenders, coupler, jack, lighting system, brake wiring, and other trailer components based on your specific build requirements.

Ideal for New Builds or Repairs

Use this package as the starting point for a new tandem axle trailer or as a convenient replacement solution when rebuilding worn or damaged running gear.

Common Applications

• Utility Trailers
• Landscape Trailers
• Equipment Trailers
• Cargo Trailers
• ATV & UTV Trailers
• Farm & Property Trailers
• Construction Trailers
• General-Purpose Tandem Trailers
• Custom Trailer Builds
• Trailer Repairs & Rebuilds

Foundation Kit vs. Rolling Kit

The Foundation Kit includes the tandem axles, springs, mounting hardware, and hanger system needed to establish the trailer’s running gear.

If you also need tires, wheels, fenders, coupler, jack, and safety chains, a Rolling Kit may be the better option. For a more complete package with blueprints, lighting, wiring, gate hardware, braking accessories, and fabrication components, consider a Master Kit.

Important Fitment Information

Please verify all trailer measurements before ordering.

• Hub Face: 89″
• Spring Center: 74″
• Individual Axle Capacity: 3,500 lbs
• Combined Axle Capacity: 7,000 lbs
• Axle Setup: 1 Idler + 1 Electric Brake

The 7,000 lb combined axle rating does not automatically mean the completed trailer is rated for 7,000 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, suspension, tires, wheels, coupler, brakes, and other hardware.

Need help confirming axle dimensions or choosing the correct kit level? Contact Highway 96 Trailers and our team can help you select the right setup for your trailer project.