The best tandem axle leaf spring setup matches the spring capacity, dimensions, axle diameter, and hanger hardware to your trailer. For a 3,500-pound axle, the SEHNSUCHT, Magorfas, and AEagle options specify 1,750-pound springs; for heavier axles, consider the SEHNSUCHT 3,000-pound springs or SOUTHWEST WHEEL 3,500-pound springs. Confirm your existing measurements and the complete trailer configuration before ordering.
| Setup | Best For | Key Detail |
|---|---|---|
| SEHNSUCHT 4-leaf | SW4B-style replacement | 1,750-pound capacity per spring |
| Magorfas 4-leaf set | Buyers comparing 3,500-pound axle springs | 60Si2Mn steel; 25-1/4-inch eye spacing |
| SEHNSUCHT 5-leaf | SW5-style replacement | 3,000-pound capacity per spring |
| SOUTHWEST WHEEL 6-leaf | Higher-capacity tandem setups | 3,500-pound capacity per spring |
| AEagle 4-leaf kit | Complete SW4B-style hardware bundle | Includes springs, U-bolts, and hanger components |
SEHNSUCHT 4-Leaf Replacement Kit
This setup is best for a trailer that uses SW4B-style, double-eye springs and a 2-3/8-inch round axle. Each spring is rated at 1,750 pounds, with four leaves, 25-1/4-inch eye-to-eye length, 1-3/4-inch width, and 9/16-inch bushings. The listed spring material is heavy-duty carbon steel with an anti-rust coating.
The package description lists U-bolts, tie plates, and nuts for the axle. Choose it if those spring dimensions and axle details match your current setup. Avoid it if your axle is square or has a different diameter. The product notes that the nut should be tightened horizontally.
Magorfas 4-Leaf Tandem Spring Set
The Magorfas set is best for buyers seeking SW4B-fit springs for a 3,500-pound trailer axle. Each spring has a stated 1,750-pound capacity. Its listed dimensions are 25-1/4 inches eye to eye, 1-3/4 inches wide, and 5/16-inch leaf thickness, with four leaves and 9/16-inch bushings. The listing specifies 60Si2Mn manganese steel and two coats of paint.
Compare the dimensions and load rating with the springs being replaced before choosing this option. Although the product title mentions a hanger and U-bolt kit, the supplied feature details do not itemize those parts. Confirm kit contents with the seller if replacement hardware is essential.
SEHNSUCHT 5-Leaf SW5 Kit
This is the better match for an SW5 replacement where the listed spring capacity is 3,000 pounds each and the axle is in the stated 5,200-to-6,000-pound range. The springs have five leaves, 25-1/4-inch eye spacing, 1-3/4-inch width, and 9/16-inch bushings. The kit description lists U-bolts and tie plates for a 3-inch round axle.
Choose this setup only after checking the axle diameter and existing spring dimensions. Its capacity and fit differ from the 1,750-pound SW4B options, so it is not a direct substitute for every tandem trailer. The listing also instructs buyers to tighten the nut horizontally.
SOUTHWEST WHEEL 7,000-Pound Kit
This kit is best for a tandem setup requiring six-leaf double-eye springs rated at 3,500 pounds each. The listing specifies four springs, each 25-1/4 inches eye to eye and 1-3/4 inches wide. It also lists a tandem hanger kit and two 3-inch U-bolt kits, making it a broad hardware package for the specified arrangement.
Check that the spring rating, dimensions, and axle configuration match your trailer before selecting it. The supplied details do not state spring bushing diameter or individual hanger dimensions, so verify those measurements if they affect your installation.
AEagle Complete SW4B Hardware Kit
AEagle is best for buyers who want four SW4B-style, 1,750-pound springs and a detailed list of tandem suspension hardware in one kit. The springs are 25-1/4 inches eye to eye, 1-3/4 inches wide, and have four leaves and 9/16-inch bushings. Listed hardware includes U-bolts for 2-3/8-inch round axles, tie plates, equalizers, hangers, shackle straps, bolts, and locknuts.
This is a poor choice for a square axle, which the listing explicitly excludes. Check that the axle is round and the spring width matches your trailer. As with the other SW4B-style setup, follow the product’s horizontal nut-tightening note.
Buying Guide: How To Choose A Tandem Axle Leaf Spring Setup
What spring capacity should you select?
Use the trailer and axle specifications to identify the required spring rating; do not choose by leaf count alone. The listed options range from 1,750 pounds per spring to 3,500 pounds per spring. These figures describe spring capacity, not a guarantee of the loaded trailer’s safe capacity. The axle, tires, wheels, frame, and other components also matter.
Which measurements need to match?
Measure eye-to-eye length, spring width, leaf count, bushing diameter, and axle diameter. Compare the measurements with the product details and your existing hardware. A similar-looking spring may not fit if its eye spacing or width differs. Also confirm whether the axle is round; the AEagle listing specifically says it does not fit square axles.
Do you need a complete hardware kit?
Replacing springs may also involve U-bolts, tie plates, equalizers, hangers, shackle straps, and bolts. Check what is included rather than relying only on a product title. For example, AEagle itemizes its hanger components, while the Magorfas feature details do not list the kit hardware individually.
Frequently Asked Questions
How do I know whether a spring fits my tandem axle trailer?
Match its capacity, eye-to-eye length, width, bushing size, and axle type to your trailer’s specifications and existing suspension.
Does a 1,750-pound spring mean the trailer can carry 7,000 pounds?
No. Spring ratings alone do not establish trailer payload or total safe capacity. Check the ratings of the complete trailer and its components.
Can I use a 3-inch axle U-bolt kit on a 2-3/8-inch axle?
Do not assume the kits are interchangeable. Select U-bolts specified for your axle diameter and confirm the fit before installation.
Should I replace the suspension hardware with the springs?
Inspect the existing components and check the replacement kit contents. Replace or obtain hardware as needed, using parts that match the axle and spring dimensions.