When you’re setting up or replacing trailer suspension, the hanger kit is one of the most important parts of the build. The hanger kit determines how your springs attach to the trailer frame and how your axles line up. The chart above breaks down hanger kits for double eye springs and slipper springs, with part numbers, equalizers, and measurements for single, tandem, and triple-axle trailers.
Double Eye Spring Hanger Kits
Double eye springs are common on utility, cargo, and lighter equipment trailers. They use shackles to connect both ends of the spring. The diagram shows how the hangers, shackles, and equalizers line up.
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Single axle kits use a front hanger, rear hanger, and shackles.
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Tandem axle kits add an equalizer in the center, allowing both axles to move and share load.
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Triple axle kits use two equalizers and additional hangers to balance three axles.
Slipper Spring Hanger Kits
Slipper springs are designed for heavier-duty trailers. Instead of shackles, one end of the spring “slips” into the hanger. This design is stronger and better for heavy loads but rides a little stiffer.
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Single axle kits are the simplest, with a front hanger and a rear slipper hanger.
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Tandem kits use an equalizer that allows the spring ends to move as the trailer flexes.
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Triple kits add a second equalizer and extra hangers to carry three axles evenly.
Understanding Hanger Spacing (A & B Dimensions)
The A and B measurements shown in the diagram are the distances between hangers that must be welded to your trailer frame.
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These dimensions are based on the suspension geometry of the specific kit (equalizer length, spring type, shackle length).
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The spring length will not equal the hanger spacing — springs extend beyond the hanger points and use shackles or slipper ends to connect.
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Correct hanger spacing ensures that the axles track straight, the equalizers pivot properly, and the suspension flexes without binding.
Important: Never weld hangers just by measuring your springs. Always follow the A/B dimensions in the kit chart. If you switch to a different spring length, you must adjust the hanger spacing as the manufacturer notes.
Choosing the Right Kit
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Count your axles – single, tandem, or triple.
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Identify your spring type – double eye or slipper.
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Check your spring width – common sizes are 1-3/4" and 2".
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Match your kit part number – the chart shows which hangers, equalizers, and spacing dimensions apply to each setup.
Pro Tip from the Shop
Mixing spring types or using the wrong hanger spacing is one of the fastest ways to cause axle misalignment, uneven tire wear, and suspension failure. Always order the correct kit for your spring style, and follow the A/B dimensions for hanger placement.
Related Products You May Need
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Double Eye Spring Hanger Kits (single, tandem, triple)
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Slipper Spring Hanger Kits (single, tandem, triple)
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Equalizers, shackles, and hanger brackets
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Leaf springs and full suspension hardware kits
Trailer Parts Unlimited – 631 TX 75 N, Huntsville TX 77320
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