A strong choice for a double-axle trailer matches the axle’s required spring capacity and dimensions, and includes enough springs and hardware for the intended installation. The Aeagle 4-Leaf Tandem Kit is a practical starting point for a 3,500-pound axle setup: it supplies four 1,750-pound springs and is listed with a U-bolt and hanger kit. This roundup also covers 5- and 6-leaf options, spring pairs, and capacities from 1,750 to 3,500 pounds per spring.
The distinction matters: a pair may replace springs on one axle, while a tandem setup commonly needs four springs. Before ordering, compare eye-to-eye length, leaf width, bushing dimensions, axle shape and the kit’s actual contents with your existing suspension.
The Aeagle 4-Leaf Tandem Kit leads for buyers seeking a complete spring set for a 3,500-pound trailer axle. It includes four double-eye springs rated at 1,750 pounds each, with a 25-1/4-inch eye-to-eye length, 1-3/4-inch width and 9/16-inch bushings. Its listed U-bolt and hanger kit makes it a more complete tandem-oriented option than the two-spring replacements here.
Confirm that your trailer uses a round axle and that the dimensions match before buying.
Our Top Picks

Four 1,750-pound springs suit a 3,500-pound axle setup; the listing also includes a U-bolt and hanger kit for a tandem installation.
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Higher Capacity KitFour springs rated at 3,000 pounds each cover the listed 5,200–6,000-pound trailer range, with an axle U-bolt kit included.
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Most LeavesFour 6-leaf springs provide 3,500-pound capacity each for 7,000-pound trailers, making this the highest stated per-spring capacity.
View on Amazon- Hardware Included Magorfas 4-Leaf Tandem Kit
Compare these trailer leaf spring options
| # | Product | Weight | Package Dimensions | Buy |
|---|---|---|---|---|
| 1 | 1. Aeagle 4-Leaf Tandem KitBest Overall | 78.8 lb | 29 x 15 x 6 in | View on Amazon |
| 2 | 2. Aeagle 5-Leaf Tandem KitHigher Capacity Kit | 98.8 lb | 29.5 x 15 x 6 in | View on Amazon |
| 3 | 3. Aeagle 6-Leaf SpringsMost Leaves | 75.7 lb | 29.05 x 12 x 6 in | View on Amazon |
| 4 | 4. Magorfas 4-Leaf Tandem KitHardware Included | 80.8 lb | 29 x 15 x 6.5 in | View on Amazon |
| 5 | 5. SEHNSUCHT 5-Leaf Kit6000-Pound SW5 Tandem Kit | 93.8 lb | 29 x 13 x 6 in | View on Amazon |
| 6 | 6. Youxmoto 6-Leaf Pair7000-Pound Axle Spring Pair | 38.2 lb | — | View on Amazon |
| 7 | 7. Aeagle 4-Leaf Spring Kit3500-Pound Axle Hardware Bundle | 28.8 lb | 28.4 x 12.2 x 4.9 in | View on Amazon |
| 8 | 8. SEHNSUCHT 4-Leaf PairDimension-Specified 5000-Pound Pair | 29.3 lb | 28 x 8 x 4.8 in | View on Amazon |
| 9 | 9. Magorfas SW4 Pair5000-Pound SW4 Replacement Pair | 29.1 lb | 28 x 8.5 x 5 in | View on Amazon |
| 10 | 10. SEHNSUCHT SW4B PairSW4B 3500-Pound Spring Pair | 24.2 lb | 28.3 x 12 x 4.8 in | View on Amazon |
Detailed Reviews: Best Double Axle Trailer Leaf Springs

#1 · Best Overall
1. Aeagle 4-Leaf Tandem Kit
- Weight: 78.8 lb
- Package Dimensions: 29 x 15 x 6 in
Best for: Complete 3500-Pound Tandem Kit.
Why it ranks #1: Four 1,750-pound springs suit a 3,500-pound axle setup; the listing also includes a U-bolt and hanger kit for a tandem installation.
The four-spring package pairs 1,750-pound-capacity springs with a U-bolt kit, giving a 3,500-pound trailer axle replacement project springs and listed mounting hardware together. Its 25-1/4-inch eye-to-eye length and SW4B replacement designation make it a specific option for round-axle setups that match those dimensions.
Each spring has four leaves, a 1-3/4-inch width, 3-inch free-open measurement, and installed 9/16-inch bushings. Those dimensions help identify whether the springs match the existing suspension, while the four-piece quantity suits a tandem arrangement. Aeagle specifies manganese steel for stable elasticity and shock absorption, and electroplated paint for rust resistance. The package also lists a U-bolt kit; installation notes say to tighten the nuts horizontally, a detail to account for during assembly.
- Four springs and a U-bolt kit are included
- 1,750-pound capacity per spring for 3,500-pound trailers
- SW4B replacement designation and 25-1/4-inch eye-to-eye length
- Electroplated coating and manganese-steel construction
- Fits round axles only, not square axles.
Skip it if you have a square axle; this spring set is specified for round axles only.
This set suits owners replacing an SW4B-style suspension on a 3,500-pound tandem trailer who want four springs and a U-bolt kit together. Check that the axle is round and the listed spring dimensions match the existing setup.
Full product details
| Brand | Aeagle |
|---|---|
| Item Weight | 78.8 pounds |
| Manufacturer | AEagle |
| Part Number | AELS0005Q4 |
| Package Dimensions | 29 x 15 x 6 inches |
Listed on Amazon as: AEagle 25-1/4" 4-Leaf 1750lb Capacity Double Eye Spring for 3500lb Trailer Axle & U-Bolt & Tandem Hanger Kit, 1.75" Width, 3" Free Open Suspension Kit Replaces SW4B, 4 PCS
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#2 · Higher Capacity Kit
2. Aeagle 5-Leaf Tandem Kit
- Weight: 98.8 lb
- Package Dimensions: 29.5 x 15 x 6 in
Best for: SW5 Four-Spring Heavy Axle Kit.
Why it ranks #2: Four springs rated at 3,000 pounds each cover the listed 5,200–6,000-pound trailer range, with an axle U-bolt kit included.
Four five-leaf springs rated at 3,000 pounds each come with an axle U-bolt kit, giving this Aeagle package a stated fit for 5,200-to-6,000-pound tandem trailer axles. The SW5 replacement reference and 25-1/4-inch length make it a targeted kit for matching round-axle suspensions.
The springs are 1-3/4 inches wide, have a 3-inch free-open measurement, and use 9/16-inch bushings. These dimensions help compare the SW5 replacement with the existing setup. Aeagle identifies manganese steel for stable elasticity and shock absorption, and electroplated paint for rust resistance. The included U-bolt kit is specified for 3-inch-diameter round trailer axles, and the listing says nuts should be tightened horizontally. Square axles are expressly excluded.
- Four springs rated at 3,000 pounds each
- Five-leaf SW5 replacement design
- U-bolt kit for 3-inch round axles included
- Electroplated coating and manganese-steel construction
- Fits round axles only, not square axles.
Skip it if you have a square axle; this SW5 kit is specified for round axles.
Choose this Aeagle kit for a round-axle tandem trailer in the stated 5,200-to-6,000-pound range when replacing SW5 springs and seeking four springs plus U-bolt hardware. Its axle shape and dimensions are key fit boundaries.
Full product details
| Brand | Aeagle |
|---|---|
| Item Weight | 98.8 pounds |
| Manufacturer | AEagle |
| Part Number | AELS0011Q4 |
| Package Dimensions | 29.5 x 15 x 6 inches |
Listed on Amazon as: Aeagle 5 Leaf 3000lb Capacity Double Eye Spring for 5200lb-6000lb Tandem Trailer Axle & U-Bolt & Hanger Kit, 25-1/4" Length, 1.75" Width, 3" Free Open Replaces for SW5, 4 PCS
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#3 · Most Leaves
3. Aeagle 6-Leaf Springs
- Weight: 75.7 lb
- Package Dimensions: 29.05 x 12 x 6 in
Best for: Four-Spring SW6 Replacement Set.
Why it ranks #3: Four 6-leaf springs provide 3,500-pound capacity each for 7,000-pound trailers, making this the highest stated per-spring capacity.
Four six-leaf springs, each rated at 3,500 pounds, give this Aeagle set the quantity and stated capacity for a 7,000-pound trailer application. Its SW6 replacement reference, round-axle limitation, and 25-1/4-inch eye-to-eye measurement make the intended fit especially important to verify against the existing suspension.
The springs are 1-3/4 inches wide, have a 3-inch free-open measurement, and use 9/16-inch bushings. These dimensions and the SW6 reference provide concrete fit details for a replacement decision. Aeagle identifies manganese-steel construction for stable elasticity and shock absorption, and an electroplated coating for rust resistance. Four springs are supplied, useful when the replacement calls for a full set. The listing explicitly excludes square axles, so this package is limited to round-axle applications.
- Four springs are included
- 3,500-pound capacity per spring for 7,000-pound trailers
- Six leaves with SW6 replacement designation
- Electroplated coating and manganese-steel construction
- Not suitable for square trailer axles.
Skip it if you have a square axle; Youxmoto's SW6-designated pair is also listed for the specified spring dimensions, but this set itself excludes square axles.
Select this set for a round-axle, 7,000-pound trailer replacement requiring four SW6-style six-leaf springs. Its stated capacity and dimensions support a specific fit decision, but square axles are expressly outside the listed compatibility.
Full product details
| Brand | Aeagle |
|---|---|
| Item Weight | 75.7 pounds |
| Manufacturer | AEagle |
| Part Number | AELS0016Q4 |
| Package Dimensions | 29.05 x 12 x 6 inches |
Listed on Amazon as: Aeagle Trailer Spring 6 Leaf Double Eye for 7000 lbs Trailer Axle Springs, 25-1/4” Length, 3500 lbs Weight Capacity Per Spring, Replacement SW6 4PCS
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#4 · Hardware Included
4. Magorfas 4-Leaf Tandem Kit
- Weight: 80.8 lb
- Package Dimensions: 29 x 15 x 6.5 in
Best for: Hardware-Included 3500-Pound Setup.
Why it ranks #4: The set of four 1,750-pound springs is listed with 14 shackle bolts and locknuts plus eight U-bolts for 3,500-pound trailers.
Four 1,750-pound-capacity springs come with specified shackle bolts, locknuts, and U-bolts, giving a 3,500-pound tandem trailer project a bundled set of suspension components. The 25-1/4-inch length and SW4B designation point to a particular replacement application, while the listing limits axle compatibility to round trailer axles.
The spring capacity is 1,750 pounds each, specified for 3,500-pound trailers, and the set contains four springs. The listed hardware includes fourteen 9/16-inch-18 shackle bolts with locknuts and eight 5-1/2-inch U-bolts measuring 1/2 inch in diameter. Having those quantities and dimensions stated can help buyers plan a suspension replacement and compare hardware with their setup. The title identifies 25-1/4-inch springs and an SW4B fit reference.
- Four springs for a 3,500-pound trailer application
- 1,750-pound capacity per spring
- Includes fourteen shackle bolts and locknuts
- Includes eight 1/2-inch-diameter U-bolts
- Compatibility is specified for round trailer axles only.
Skip it if you need springs for a 7,000-pound axle; Youxmoto's six-leaf 3,500-pound-per-spring pair is specified for that capacity.
Choose this Magorfas set if your round-axle tandem trailer calls for the listed SW4B, 25-1/4-inch spring format and you want shackle and U-bolt hardware included. Its stated spring capacity is for 3,500-pound trailers.
Full product details
| Brand | Magorfas |
|---|---|
| Item Weight | 80.8 pounds |
| Item model number | MFLS0005Q4 |
| Manufacturer | Magorfas |
| Part Number | MFLS0005Q4 |
| Package Dimensions | 29 x 15 x 6.5 inches |
Listed on Amazon as: Tandem Trailer Leaf Spring 4 Leaf Double Eye 1750 lbs Cap for 3500 lbs Axle Suspension, Hanger & U-Bolt kit 25-1/4" Length fits for SW4B, for Round Trailer Axles- Set 4
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#5
5. SEHNSUCHT 5-Leaf Kit
- Weight: 93.8 lb
- Package Dimensions: 29 x 13 x 6 in
Best for: 6000-Pound SW5 Tandem Kit.
Why it ranks #5: Its 3,000-pound springs are specified for standard 5,200–6,000-pound trailer axles, and the listing describes a tandem suspension kit.
Five-leaf springs rated at 3,000 pounds each are paired with a U-bolt and hanger kit, giving this SEHNSUCHT package a stated role on standard 5,200-to-6,000-pound trailer axles. The SW5 replacement reference and 25-1/4-inch eye-to-eye length narrow the application to matching suspension layouts.
Each spring measures 1-3/4 inches wide, has a 3-inch free-open measurement, and uses 9/16-inch bushings. Together with the five-leaf construction and 3,000-pound individual rating, those specifications help buyers compare the set with an SW5 replacement requirement. The listed hanger and U-bolt kit groups suspension components with the springs for a tandem project. The instructions also specify horizontal nut tightening, so assembly requires attention to that orientation.
- 3,000-pound capacity per spring
- Five-leaf construction for standard 5,200-to-6,000-pound axles
- U-bolt and hanger kit included
- SW5 replacement reference and 25-1/4-inch length
- The listing specifies horizontal nut tightening during assembly.
Skip it if you need a 3,500-pound-axle spring set; SEHNSUCHT's SW4B four-leaf pair is specified for that application.
This kit suits a tandem-trailer owner replacing SW5 springs on a listed 5,200-to-6,000-pound axle and wanting hanger and U-bolt components bundled. Confirm the spring dimensions match, and follow the horizontal nut-tightening note during assembly.
Full product details
| Brand | SEHNSUCHT |
|---|---|
| Item Weight | 93.8 pounds |
| Manufacturer | SEHNSUCHT |
| Part Number | LS0011 |
| Package Dimensions | 29 x 13 x 6 inches |
Listed on Amazon as: Replacement for SW5 5 Leaf Trailer Leaf Spring, 6000LB Tandem Trailer Axle Suspension Kit with 3000lb Capacity Double Eyes Leaf Springs, 2 U-Bolt and Hanger Kit
View on AmazonWhy it ranks #6: Two 6-leaf springs rated at 3,500 pounds each fit a 7,000-pound trailer axle, but the listing supplies a pair rather than four springs.
Six leaves and a stated 3,500-pound capacity per spring make this two-piece Youxmoto set the higher-capacity option here, specified for trailers with 7,000-pound axles. The 25-1/4-inch eye-to-eye length and SW6 replacement reference help identify the intended suspension fit before a buyer selects the pair.
Each spring measures 1-3/4 inches wide, has a 3-inch free-open measurement, and uses 9/16-inch bushings. These details, alongside the 25-1/4-inch eye-to-eye length, help compare the replacement with the existing suspension. The six-leaf construction is tied in the listing to higher load capacity, while the steel-plate material is described as supporting stable transmission. An added rust-proof coating is specified for harsher environments. The package contains two springs, rather than a complete four-spring tandem set.
- 3,500-pound capacity per spring for 7,000-pound trailers
- Six-leaf construction
- 25-1/4-inch eye-to-eye length and SW6 fit reference
- Rust-proof coating is specified
- Two springs are included, not a complete four-spring set.
Skip it if you need four springs for a full tandem replacement; Aeagle's SW6 four-piece set includes four six-leaf springs.
This pair fits buyers replacing SW6-style springs on a 7,000-pound trailer axle who need two 3,500-pound-capacity springs. Account for the two-piece quantity and compare the listed eye length, width, and bushing diameter with the suspension.
Full product details
| Brand | Youxmoto |
|---|---|
| Item Weight | 38.2 pounds |
| Item model number | LFLS0015-LYF |
| Manufacturer | Youxmoto |
| Part Number | LFLS0015-LYF |
| Model | LFLS0015-LYF |
| Dimensions | 12.2 x 3.93 x 28.34 inches |
Listed on Amazon as: Youxmoto Trailer Leaf Springs 3500lbs for 7000lbs Axle- 6 Leaves Double Eye, 25-1/4" L, 1-3/4" Width, Fits SW6; Heavy Duty Steel Plate Springs, 2pcs
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#7
7. Aeagle 4-Leaf Spring Kit
- Weight: 28.8 lb
- Package Dimensions: 28.4 x 12.2 x 4.9 in
Best for: 3500-Pound Axle Hardware Bundle.
Why it ranks #7: The pair of 1,750-pound springs includes U-bolts and tie plates for a 2-3/8-inch round axle, but does not provide four springs.
Two 1,750-pound-capacity springs arrive with a U-bolt kit and tie plates, giving this Aeagle package a bundled option for a 3,500-pound round-axle replacement. The SW4B reference, 25-1/4-inch length, and hardware dimensions identify the specific suspension setup the listing addresses.
Each four-leaf spring has a 1-3/4-inch width and 3-inch free-open measurement, with the listing specifying 9/16-inch bushings. The 1,750-pound rating per spring is for a 3,500-pound trailer axle. The kit lists four 5-1/2-inch U-bolts, tie plates for 1-3/4-inch leaf springs, and eight hex nuts; its U-bolts are stated for 2-3/8-inch-diameter round axles. These included pieces can consolidate parts for the listed replacement, but axle dimensions remain a fit boundary.
- Two springs rated at 1,750 pounds each
- U-bolt kit and tie plates included
- SW4B replacement reference
- U-bolts specified for 2-3/8-inch round axles
- The package contains two springs, not four for a full tandem replacement.
Skip it if you need four springs for a complete tandem replacement; Aeagle's SW4B four-piece set includes four springs and a U-bolt kit.
This bundle fits buyers replacing two SW4B springs on a 3,500-pound round-axle trailer who want U-bolts and tie plates included. Check the stated 2-3/8-inch axle and spring dimensions against the existing setup.
Full product details
| Brand | Aeagle |
|---|---|
| Item Weight | 28.8 pounds |
| Manufacturer | AEagle |
| Part Number | AELS0003Q2 |
| Package Dimensions | 28.4 x 12.2 x 4.9 inches |
Listed on Amazon as: Aeagle 25-1/4" 4-Leaf 1750lb Capacity Double Eye Spring for 3500lb Trailer Axle & U-Bolt Kit, 1.75" Width, 3" Free Open, Replaces for SW4B, 2PCS
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#8
8. SEHNSUCHT 4-Leaf Pair
- Weight: 29.3 lb
- Package Dimensions: 28 x 8 x 4.8 in
Best for: Dimension-Specified 5000-Pound Pair.
Why it ranks #8: This two-spring set offers 2,500-pound capacity per spring and broad listed replacement references, though a tandem setup may require another pair.
This SEHNSUCHT pair combines a 2,500-pound rating per spring with a broad set of replacement references, including SW4, UNA218, PR4, and 93181. The 25-1/4-inch eye-to-eye length and stated 5,000-pound axle application help buyers narrow compatibility across several listed spring designations.
Each spring has four leaves, a 1-3/4-inch width, and a 3-inch free-open measurement. The listing gives a 9/16-inch eye diameter with the bushing and 11/16 inch without it, plus 3/8-inch leaf thickness. Those details support direct measurement comparisons during replacement selection. Capacity is stated at 2,500 pounds per spring for a standard 5,000-pound trailer axle. The two-piece quantity suits a spring-pair replacement, while the supplied description does not identify a hardware kit.
- 2,500-pound capacity per spring for 5,000-pound axles
- Lists several replacement references, including SW4 and PR4
- Specifies eye diameters with and without bushings
- Four leaves and 3/8-inch leaf thickness
- Only two springs are included; mounting hardware is not listed.
Skip it if you need a four-spring package with mounting hardware; Aeagle's SW4B four-piece set includes a U-bolt kit.
This pair suits owners matching a 5,000-pound axle spring to one of the listed replacement references and who value detailed eye and leaf measurements. Plan separately for any hardware not already available.
Full product details
| Brand | SEHNSUCHT |
|---|---|
| Item Weight | 29.3 pounds |
| Manufacturer | SEHNSUCHT |
| Part Number | LS0007 |
| Package Dimensions | 28 x 8 x 4.8 inches |

#9
9. Magorfas SW4 Pair
- Weight: 29.1 lb
- Package Dimensions: 28 x 8.5 x 5 in
Best for: 5000-Pound SW4 Replacement Pair.
Why it ranks #9: The pair is rated at 2,500 pounds per spring for a 5,000-pound axle, but the supplied specifications give less dimensional detail than several alternatives.
A 2,500-pound-per-spring rating places this Magorfas two-spring set in the 5,000-pound trailer-axle category, with a 25-1/4-inch length and SW4 replacement reference identifying its intended application. Its concise listing makes the capacity and pair quantity central details for a buyer comparing replacement springs.
The set contains two springs, each specified at 2,500 pounds for 5,000-pound trailers. That stated capacity helps distinguish it from lower-capacity SW4B options when selecting a spring pair for a listed axle class. The title gives a 25-1/4-inch length and SW4 fit reference, useful starting points for comparing a replacement with existing springs. The supplied information does not provide leaf width, bushing diameter, or included mounting hardware, so those details cannot be assessed from this listing.
- 2,500-pound capacity per spring
- Specified for 5,000-pound trailer axles
- Two-spring set
- 25-1/4-inch length and SW4 fit reference
- The supplied specifications omit spring width and bushing dimensions.
Skip it if you need detailed bushing and width specifications before choosing; SEHNSUCHT's SW4-designated pair lists both dimensions.
Consider this Magorfas pair for a 5,000-pound trailer axle when the SW4 reference and 25-1/4-inch length match your replacement needs. The supplied specifications are brief, so buyers needing additional dimensions should use a more detailed listing.
Full product details
| Brand | Magorfas |
|---|---|
| Item Weight | 29.1 pounds |
| Item model number | MFLS0007Q2 |
| Manufacturer | Magorfas |
| Part Number | MFLS0007Q2 |
| Package Dimensions | 28 x 8.5 x 5 inches |
Listed on Amazon as: Trailer Leaf Spring 4 Leaf Double Eye 2500 lbs Cap for 5000 lbs Axle Suspension 25-1/4" Length fits for SW4 – Set 2
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#10
10. SEHNSUCHT SW4B Pair
- Weight: 24.2 lb
- Package Dimensions: 28.3 x 12 x 4.8 in
Best for: SW4B 3500-Pound Spring Pair.
Why it ranks #10: These two 1,750-pound springs match the 3,500-pound axle class, but the pair alone is less complete for a double-axle replacement.
Two four-leaf springs rated at 1,750 pounds each give this SEHNSUCHT pair a clearly stated application for a 3,500-pound trailer axle. Its SW4B replacement reference and 25-1/4-inch eye-to-eye length distinguish it as a spring-only option for buyers sourcing the remaining suspension hardware separately.
Each spring is 1-3/4 inches wide, has a 3-inch free-open measurement, and includes two installed 9/16-inch bushings; the listed leaf thickness is 5/16 inch. These measurements help assess whether the pair matches an existing SW4B suspension. The 1,750-pound rating per spring is specified for a 3,500-pound axle, and the package contains two pieces. It does not list a U-bolt or hanger kit, so plan the replacement around the spring pair itself.
- Two springs rated at 1,750 pounds each
- Specified for a 3,500-pound trailer axle
- SW4B replacement reference
- Includes installed 9/16-inch bushings
- The package is a two-spring pair, not a complete tandem kit.
Skip it if you need four springs and hardware together; Aeagle's SW4B four-piece package includes a U-bolt kit.
This pair suits an SW4B replacement on a 3,500-pound trailer axle when two springs are needed and hardware is already accounted for. Use the stated width, length, bushing diameter, and leaf thickness to assess the match.
Full product details
| Brand | SEHNSUCHT |
|---|---|
| Item Weight | 24.2 pounds |
| Manufacturer | SEHNSUCHT |
| Part Number | LS0002 |
| Package Dimensions | 28.3 x 12 x 4.8 inches |
Listed on Amazon as: SEHNSUCHT Trailer Leaf Spring, 4 Leaf 1750lb Capacity Double Eye Leaf Springs for 3500lb Trailer Axle, 25-1/4"L, 1.75" Width, 3” Free Open of Leaf Spring, Replace for SW4B, 2 Pieces
View on AmazonAvoiding axle and fitment mismatches
Check axle shape and spring dimensions before treating a replacement reference as proof of fit. Aeagle explicitly says its SW4B and SW6 springs fit round axles only and do not fit square axles; the 2-piece Aeagle 4-Leaf Spring Kit further specifies a 2-3/8-inch round axle for its U-bolt kit. A spring can have the correct capacity and still be incompatible if its mounting hardware or axle shape differs.
Compare the existing spring’s eye-to-eye length, leaf width, bushing size and free-open measurement with the listing: several options specify 25-1/4 inches, 1-3/4 inches, 9/16-inch bushings and 3 inches of free open. Also verify the axle diameter and hardware dimensions against your trailer.
The key trap is assuming that a shared SW replacement code guarantees every surrounding component will fit.
Why spring count changes the replacement plan
A listed spring capacity describes each spring, not the number of springs supplied or the capacity of the whole trailer. For example, the Aeagle 4-Leaf Tandem Kit includes four springs rated at 1,750 pounds each, while the SEHNSUCHT SW4B Pair supplies two springs with the same per-spring rating. Several other listings also sell pairs, including the Youxmoto 6-Leaf Pair at 3,500 pounds per spring.
That distinction affects how many units you need for a tandem replacement and whether you are replacing one axle or the whole suspension set. Do not infer a trailer’s legal or safe carrying capacity by multiplying the spring rating alone: the axle, tires, frame, hangers and other components also matter, and their ratings are not provided here.
Confirm the complete system’s ratings and the contents of each kit before ordering.
How to Choose Double-Axle Trailer Leaf Springs
Capacity per spring
Choose springs whose stated capacity matches the axle and trailer application, rather than comparing leaf counts alone. These listings range from 1,750 pounds per spring for 3,500-pound trailer axles to 2,500 pounds for 5,000-pound axles, 3,000 pounds for 5,200–6,000-pound axles, and 3,500 pounds for 7,000-pound trailers. The lower-capacity 4-leaf choices suit the listed 3,500-pound class; 5-leaf options target the 5,200–6,000-pound range; and the 6-leaf choices cover the 7,000-pound class.
These are stated applications, not a substitute for checking your trailer’s component ratings. Match the specification to your setup, and do not select a higher rating solely because it appears more robust.
Number of springs and kit contents
Look for enough springs and compatible hardware for the repair you plan to make. The Aeagle 4-Leaf Tandem Kit and Aeagle 5-Leaf Tandem Kit each list four springs, while several alternatives provide only two. A pair may be appropriate when replacing springs on one axle, but a full tandem suspension replacement typically involves four springs; verify your trailer’s layout and repair scope.
Included hardware also varies: the Aeagle 4-Leaf Tandem Kit lists a U-bolt and hanger kit, and the Magorfas 4-Leaf Tandem Kit lists shackle bolts, locknuts and eight U-bolts. Buyers completing a broader tandem repair may favour a four-spring kit with relevant hardware.
Buyers replacing only a pair should check that the supplied hardware matches their existing axle and hangers.
Dimensions and axle compatibility
Compare the spring’s mounting dimensions and axle type with the parts already on your trailer. Many listings specify a 25-1/4-inch eye-to-eye length and 1-3/4-inch leaf width; several also list a 3-inch free-open measurement and 9/16-inch bushings. The SEHNSUCHT 4-Leaf Pair for 5,000-pound axles gives a 3/8-inch leaf thickness, while the 3,500-pound SEHNSUCHT pair lists 5/16 inch.
Aeagle states that its SW4B and SW6 springs fit round axles only, and the Aeagle 2-piece kit specifies hardware for a 2-3/8-inch round axle. Buyers replacing a matching round-axle setup can use these details to narrow the choices; anyone with a square axle or different mounting geometry should verify fitment before ordering.
Which Double-Axle Leaf Springs Should You Choose?
For a 3,500-pound axle and a four-spring tandem replacement, choose the Aeagle 4-Leaf Tandem Kit: it supplies four 1,750-pound springs and lists a U-bolt and hanger kit. If your stated application is 5,200–6,000 pounds, the Aeagle 5-Leaf Tandem Kit provides four 3,000-pound springs and an axle U-bolt kit. For a 7,000-pound trailer axle, the Aeagle 6-Leaf Springs offer four springs rated at 3,500 pounds each; the Youxmoto 6-Leaf Pair has the same per-spring capacity but supplies only two.
For replacing a pair on a 5,000-pound setup, consider the SEHNSUCHT 4-Leaf Pair or Magorfas SW4 Pair. In every case, confirm axle shape, dimensions, spring count and hardware compatibility before ordering.
Related Buying Guides
Frequently Asked Questions
How can I confirm whether my trailer has a round or square axle?
Check the axle tube’s cross-section where it is visible, or consult the trailer or axle documentation for its shape. Do not infer axle shape from the springs alone. Compare the confirmed axle type with the product’s stated fit, and verify dimensions and hardware compatibility before ordering.
How do I check whether my trailer needs two springs or four?
Count the springs currently installed and check the trailer’s suspension layout and replacement requirements. A tandem setup may use four springs, while some listings provide only a pair. Match the required count to the product quantity, and confirm the arrangement with the trailer or axle documentation before ordering.
When should trailer leaf springs be replaced as a pair or set?
Replace springs in pairs on the same axle so both sides have matched components. For a tandem suspension, check all four springs and replace the full set when the set requires matched replacements or multiple springs are worn or damaged. Confirm the required spring count and specifications for your trailer.
Which spring dimensions should I compare before ordering?
Compare the listed eye-to-eye length, spring width, and bushing dimensions with the springs currently fitted or the trailer documentation. The products here include different capacities and quantities, so matching length alone is not enough. Confirm that the replacement’s dimensions and stated application suit your suspension.
How do I know whether the included hardware will fit my trailer?
Check what hardware the listing includes, then compare it with your axle and hanger arrangement and the trailer’s requirements. The listed kits differ: some include U-bolts, hangers, or both, while others are spring-only options. Confirm compatibility before ordering rather than assuming included hardware fits.
Final Words
For a 3,500-pound axle needing four tandem springs, the Aeagle 4-Leaf Tandem Kit is the clearest match: it includes four 1,750-pound springs plus listed U-bolt and hanger hardware. For stated 5,200–6,000-pound or 7,000-pound applications, compare the corresponding Aeagle set’s capacity and quantity. If replacing a pair on a 5,000-pound setup, consider the SEHNSUCHT or Magorfas pair.
Verify axle shape, dimensions, spring count, and hardware fit before ordering.


