SEHNSUCHT trailer leaf spring kit — 2-piece 1,750 lb double-eye springs with U-bolts & hangers for 3,500 lb axle

SEHNSUCHT's kit delivers two 1,750 lb double-eye leaf springs plus U-bolts and hangers designed to restore a 3,500 lb single-axle trailer suspension.

This replacement bundle contains everything needed to upgrade or repair a standard 3,500 lb trailer axle: two four-leaf springs built for 1,750 lb each, a matched U-bolt and tie plate set sized for 2 3/8" round axles, and a complete hanger/shackle assortment for 1-3/4" leaf packs. Components are heat-treated carbon steel with an anti-corrosion finish and come with installed bushings for quicker installation. The kit is intended as a direct substitute for SW4B-style springs and includes clear hardware counts and dimensions so you can confirm fit before purchase.

How do these springs match my trailer's capacity?

Each spring in this set is rated for 1,750 lb, so the paired assembly supports a typical 3,500 lb single trailer axle when mounted as intended. Ratings assume even load distribution across the axle and correct installation with supplied hardware.

• Per-spring capacity: 1,750 lb
• Intended axle rating: 3,500 lb (combined)
• Leaf pack: 4 leaves, 5/16" thickness per leaf
• Designed as direct SW4B replacements

What exact dimensions and fittings are included?

The springs measure 25-1/4" eye-to-eye with a 3" free arch and 1-3/4" leaf width; each spring includes two 9/16" bushings already installed. The U-bolt kit fits 2 3/8" round axles and the hanger kit contains both tall and short hangers plus shackle straps and bolts for standard mounting.

• Spring eye-to-eye: 25-1/4"; free arch: 3"
• Leaf width: 1-3/4"; bushing dia: 9/16" (2 per spring)
• U-bolts: 4 × 5-1/2" long, 1/2" thread; inside curvature ≈ 2.44"
• Hangers: 2 × 3" tall, 2 × 2.1" tall; shackle straps and bolts included

What materials and corrosion protection are used?

The spring leaves are constructed from heavy-duty carbon steel and undergo heat treatment to maintain load stability and resist deformation. An extra anti-rust coating is applied to exposed steel surfaces to extend service life in wet or salty environments.

• Material: heat-treated carbon steel for durability
• Finish: anti-corrosion coating on leaves and hardware
• Bushings: 9/16" diameter, pre-installed for faster assembly

Which parts of the kit require attention during installation?

Proper torque orientation is important for the supplied nuts—tighten horizontally to ensure the hardware seats correctly and to avoid altering spring behavior. Also verify axle diameter and hanger alignment before final tightening to prevent premature wear or misalignment.

• Tighten nuts horizontally as instructed to maintain performance
• Confirm axle is 2 3/8" diameter for U-bolt compatibility
• Check hanger and shackle positions for correct spring alignment

Who this is for: This SEHNSUCHT kit is intended for trailer owners, repair shops, and fleet managers needing a complete SW4B-style replacement for a 3,500 lb single axle. It suits users who want pre-bushed springs and a full hardware set—ideal when replacing both springs and mounting hardware to restore ride height, stability, and safe load carrying on utility, boat, landscape, or enclosed trailers.