Best 4 Leaf Trailer Springs for Reliable Suspension and Load Handling
Choosing the right 4 leaf trailer spring is essential for maintaining trailer stability, ride quality, and load capacity. This guide highlights five high-quality options, covering different axle ratings, fitments (SW4 and SW4B), and materials. Each product emphasizes strong manganese steel construction, corrosion resistance, and precise dimensions to match common trailer configurations.
| Product | Leaf Count | Capacity (per spring) | Fitment | Length |
|---|---|---|---|---|
| Magorfas Trailer Leaf Spring 4 Leaf Double Eye 2500 lbs Cap | 4 | 2500 lbs | SW4 | 25-1/4″ |
| Youxmoto 3500lb Single Trailer Axle Suspension Kit 4-Leaf | 4 | 1750 lbs per spring | SW4B | 25-1/4″ |
| SEHNSUCHT Trailer Leaf Spring 4 Leaf 1750lb 2 Pieces | 4 | 1750 lbs per spring | SW4B | 25-1/4″ |
| Aeagle 25-1/4″ 4-Leaf 1750lb Capacity | 4 | 1750 lbs per spring | SW4B | 25-1/4″ |
| TRAILER SUPPLIES Pair of 24-5/8″ 4-Leaf Slipper Springs | 4 | 1000 lbs per spring | Various 2,000 lb axles | 24-5/8″ |
Magorfas Trailer Leaf Spring 4 Leaf Double Eye 2500 lbs Cap
The Magorfas 4-leaf trailer spring set yields a 25-1/4″ eye-to-eye length and a 3″ free open with a 1-3/4″ leaf width. Each spring handles up to 2500 lbs, designed for 5000 lbs axle configurations. The springs use manganese steel to provide strength, flexibility, and durability with corrosion-resistant dual-coat paint. A suitable choice for SW4 trailers requiring robust performance and reliable replacement parts.
Magorfas Trailer Leaf Spring 4 Leaf Double Eye 1750 lbs Cap
This Magorfas 4-leaf, 25-1/4″ eye-to-eye spring is designed for SW4B trailers with a 3500 lbs axle rating. Each spring provides 1750 lbs of capacity, with a 3″ free open and a 1-3/4″ leaf width. Like the other Magorfas offerings, it uses 60Si2Mn manganese steel and features a dual-coat protective finish for improved corrosion resistance. Ideal for replacing worn SW4B springs on mid-range trailers.
Youxmoto 3500lb Single Trailer Axle Kit 4-Leaf
Youxmoto offers a 4-leaf, 25-1/4″ long spring kit with 1750 lbs per spring capacity, tailored for 3,500 lbs round axles (SW4B). The kit includes U-bolts, tie plates, and hardware to facilitate direct replacement and secure installation. A robust kit designed for longevity, with careful dimensioning to ensure alignment, fit, and performance in standard trailer applications.
SEHNSUCHT Trailer Leaf Spring 4 Leaf 1750lb 2 Pieces
Two-piece SEHNSUCHT 4-leaf springs meet SW4B requirements with a 25-1/4″ eye-to-eye and 3″ free open. Each spring provides 1750 lbs capacity for a 3500 lbs trailer axle, with 1-3/4″ leaf width and 9/16″ bushings. Made from heavy-duty carbon steel with anti-rust coating, these springs are designed for corrosion resistance and long-term service life. Suitable for replacing standard 3500 lbs axle springs on compatible trailers.
Aeagle 25-1/4″ 4-Leaf 1750lb Capacity
Aeagle delivers a 4-leaf spring kit with a 25-1/4″ eye-to-eye, 1.75″ width, and 3″ free open. With 1750 lbs per spring capacity for 3500 lbs trailers, this SW4B-compatible option includes a U-bolt kit and hardware for installation. The design emphasizes secure fastening and durable performance, a practical choice for standard replacement on compatible SW4B trailers.
TRAILER SUPPLIES Pair of 24-5/8″ 4-Leaf Slipper Springs
Trailer Supplies offers a pair of 24-5/8″ four-leaf springs rated at 1,000 lbs per spring (2,000 lbs per axle). These are designed as direct replacements for UNA-179, WH4, and Dexter 4341-10, fitting many 2,000 lb axles from major manufacturers. Each spring features a standard 1-3/4″ width, 3″ arch, and 9/16″ nylon bushings pre-installed. A solid option for light-duty, low-weight trailers seeking OEM-compatible replacements.
Buying Guide
Key purchase considerations include axle capacity and trailer type. Align spring capacity with axle rating to prevent overloading the suspension. For SW4 vs SW4B, confirm eye-to-eye length and bushings size (9/16″ is common). Material matters: manganese steel (60Si2Mn) offers strength and fatigue resistance, while anti-rust coatings extend service life. Look for pre-installed bushings and included U-bolts to ease installation. Check free open (around 3″) to ensure adequate flex under load. For replacement accuracy, match leaf count, width (1-3/4″), and leaf thickness (5/16″ or 3/8″) to original springs. If uncertain, consult trailer manufacturer guidelines or a suspension specialist. Also consider corrosion resistance in harsh environments and the availability of compatible hanger kits and U-bolts.
Comparison snapshot:
- Highest capacity per spring: 2500 lbs (Magorfas SW4) for heavier loads; supports up to 5000 lbs per axle.
- Most complete kit: Youxmoto and Aeagle bundles include U-bolts and hardware for SW4B compatibility.
- Best value for light-duty trailers: TRAILER SUPPLIES pair, 1000 lbs per spring, fits common 2,000 lb axles.
- Corrosion resistance emphasis: Both Magorfas and SEHNSUCHT feature dual-coat protective finishes.
- Ease of replacement: SW4B-compatible kits with two-piece or four-leaf designs designed for straightforward swaps.
Always verify dimensions against your trailer’s leaf springs: eye-to-eye length, leaf width, and bushing diameter are critical for proper seating and performance. Use the buying guide to compare multiple options, ensure correct installation hardware, and choose a kit that matches your trailer’s axle rating and mounting style.