Aeagle 25-1/4" 4-Leaf Double-Eye Trailer Spring Kit — 1,750 lb per Spring, 3" Free-Open, Includes U-Bolts & Tandem Hanger (4 PCS)

AEagle 25-1/4" 4-leaf double-eye spring kit supplies 1,750 lb capacity per spring and includes U-bolts and a tandem hanger set to support a 3,500 lb trailer axle.

This complete suspension kit is a direct-fit replacement for round-axle 3,500 lb trailer systems that accept SW4B-style springs. Each steel spring measures 25-1/4" eye-to-eye, has a 3" free-open length and four leaves built on a 1.75" top-width with 5/16" leaf thickness. The kit bundles four springs, mounting hardware, U-bolts sized for 2-3/8" round axles, tie plates, and a tandem hanger/equalizer pack so you receive everything needed for a coordinated axle installation.

Will these springs fit my trailer axle?

These AEagle springs are designed for round trailer axles only and replace SW4B-style parts. They are not compatible with square axles; confirm your axle is 2-3/8" round diameter and your trailer rating matches 3,500 lb axles.

• Eye-to-eye length: 25-1/4"
• Free-open length: 3"
• Top leaf width: 1.75"; leaf thickness: 5/16"
• Capacity: 1,750 lb per spring (4 springs for 3,500 lb axle setups)

What hardware is included and how does it help installation?

The kit contains all primary mounting pieces so you won’t need to source staples separately. Included are U-bolts, tie plates, hex nuts, two equalizers, hangers, shackle straps, and shackle bolts with locknuts to assemble a tandem axle suspension layout.

• U-bolts: 8 × 5-1/2" long, 1/2" dia, thread length 1.97"
• Tie plates: 4 plates sized for 1-3/4" leaf springs
• Tandem hardware: 2 equalizers, 6 hangers, 8 shackle straps, shackle bolts and locknuts
• Nuts: 16 × 1/2"-20 hex nuts for secure clamping

How durable and long-lasting are these components?

AEagle forms these springs from quality raw steel and applies an anti-rust coating for improved corrosion resistance in road and storage conditions. Every kit is tested before shipping and backed by a 12-month warranty for added confidence.

• Anti-rust coating on springs and hardware
• High-quality steel construction chosen for strength
• Pre-shipment testing and 12-month warranty included
• Two 9/16" bushings installed per spring for reduced wear

Are there installation tips or important notes to know?

Follow torque and alignment guidance for best ride and safety performance; tighten the included nuts horizontally as specified to avoid uneven forces. Verify shackle bolt lengths and confirm equalizer orientation when assembling the tandem hangers.

• Tighten nuts horizontally to ensure proper spring seating
• Confirm equalizer and hanger placement for tandem axles
• Match bushings and bolt sizes included to your mounting hardware
• Not suitable for square axles—only round 2-3/8" diameter axles

Who is this for: This AEagle suspension kit is intended for trailer owners, small-fleet operators, and DIY mechanics who need a full replacement leaf-spring assembly for a 3,500 lb-rated round axle. It’s especially useful when you want a complete set—springs plus U-bolts and tandem hanger hardware—delivered together for straightforward installation and dependable on-road performance.