Aeagle 4-Leaf Double-Eye Trailer Springs for 3,500 lb Axle — 25-1/4" Eye-to-Eye, 1,750 lb Each (Pair)

Aeagle 4-leaf double-eye trailer springs (pair) provide 1,750 lb capacity each to rebuild or replace the suspension on a 3,500 lb tandem-axle trailer using round axles.

These two replacement leaf springs are engineered to match common light-trailer requirements while offering corrosion resistance and factory-installed bushings for straightforward installation. Each spring features a 25-1/4" eye-to-eye length, 3" free open height, and 1-3/4" leaf width, making them suitable for many 3,500 lb-rated trailer setups that accept round axles and double-eye spring hangers. The kit includes two springs and two bushings per spring and is sold as a set that replaces part number SW4B (not for square axles).

How do these springs support a 3,500 lb trailer?

Each Aeagle spring is rated for 1,750 lb, and when fitted as a matching pair across the axle they provide the correct load capacity for a 3,500 lb gross axle weight. The spring pack of four leaves balances load distribution and resists sag under normal towing conditions.

• Rated capacity: 1,750 lb per spring (pair supports 3,500 lb axle).
• Four-leaf construction for step stiffness and load control.
• 5/16" leaf thickness to maintain spring rate and longevity.
• Includes two bushings per spring for immediate fitment.

Will these fit my trailer axle and hangers?

These springs are designed specifically for round axles and double-eye hangers; they will not fit square-axle setups. Confirm your trailer uses round-axle spring hangers and that the eye-to-eye length and free height match your existing springs or hanger spacing before ordering.

• Eye-to-eye length: 25-1/4" — measure hanger centers to confirm fit.
• Free open height: 3" — compare to existing spring free arch.
• Eye diameter and bushings: 9/16" bushings installed for standard hanger bolts.
• Width: 1-3/4" leaf width to match common hanger seats for double-eye springs.

How durable and corrosion-resistant are these springs?

Aeagle applies an anti-rust coating to each leaf pack and selects robust raw materials to extend service life under road and weather exposure. The coating and manufacturing quality reduce the risk of premature rust and maintain strength under repeated loads, while the assembled bushings cut down on immediate post-installation fitting work.

• Anti-rust coating for improved corrosion resistance.
• High-quality raw materials for reliable tensile strength.
• Factory-installed bushings speed installation and alignment.
• Tested before shipping and backed by a 12-month warranty.

What measurements and parts should I check before replacing springs?

Before buying, measure your current spring eye-to-eye length, free arch height, leaf width, and check whether your axle/hangers accept double-eye springs for round axles. Verify bushings and hanger bolt size—this kit uses 9/16" bushings—to avoid surprises when you go to install.

• Eye-to-eye: 25-1/4" — hanger center-to-center must match.
• Free open (arch) height: 3" — ensures proper ride height and clearance.
• Leaf width: 1-3/4" and 5/16" leaf thickness — match hanger seat and clip sizes.
• Bushing diameter: 9/16" — confirm with hanger bolt size.

Who this is for: This pair of Aeagle 4-leaf double-eye springs is aimed at trailer owners, repair shops, and fleet managers who need an OEM-style replacement for round-axle, 3,500 lb-rated trailers. Choose this kit if you need matching pair springs with pre-installed bushings, a proven load rating of 1,750 lb per spring, and anti-rust protection. Do not use these on square-axle setups — check your existing spring specs and hanger configuration before purchasing.