OZISENS Trailer Axle Equalizer & Shackle Kit 7-3/4" Equalizers, 3-1/8" Shackles for 3500–5200 lb Tandem Axles

OZISENS Trailer Axle Equalizer 312L Shackle Kit is a complete suspension repair and upgrade set designed for tandem-axle trailers rated 3,500 to 5,200 lb, including equalizers, shackle straps, bolts, nuts and nylon bushings.

This kit provides the core hardware needed to maintain or rebuild the spring-to-axle linkages on tandem trailer suspensions. All components arrive pre-finished with a black oxide paint to resist corrosion, and the assortment includes sizes commonly used for double-eye leaf springs so you can replace worn parts without hunting for individual pieces.

What parts are included and what sizes should I expect?

The OZISENS kit bundles two 7-3/4" equalizers with eight 3-1/8" shackle straps, plus the fasteners and bushings required to install them. Bolt lengths, bushing inner and outer diameters, and nut thread specs are matched to typical trailer spring hardware for 3,500–5,200 lb axles.

• 2 x 7-3/4" equalizer bars (model EQ-E1)
• 8 x 3-1/8" shackle straps with 3-1/8" hole spacing
• 14 x bolts (approximately 3-3/8" length) and 14 x 9/16"-18 self-locking nuts
• 14 x nylon bushings, 9/16" I.D. and 11/16" O.D. for reduced play and noise

How does this kit improve trailer suspension performance?

Replacing ragged shackles and worn equalizers restores correct alignment and motion for leaf springs, cutting down on clunking, uneven wear and stress on the axle. The included nylon bushings reduce metal-to-metal contact, which lowers noise and extends component life.

• Precision-fit bushings reduce slop and vibration
• Black oxidized finish helps resist rust in exposed environments
• Complete fastener set simplifies installation or full replacement

Will these parts fit my trailer and how do I confirm compatibility?

This kit targets tandem-axle trailers with double-eye leaf springs in the 3,500–5,200 lb range, but it's important to verify measurements. Check your current equalizer length, shackle hole spacing and bolt diameters before ordering; the kit's critical dimensions are listed to make matching straightforward.

• Measure existing equalizer length and shackle hole spacing (3-1/8" in this kit)
• Confirm bolt diameter and bushing I.D. match your trailer (9/16" I.D.)
• Compare axle and spring ratings—this kit suits 3,500–5,200 lb setups

What should I know about installation and maintenance?

Installation requires basic mechanical tools and safe lifting support for the trailer. Replace components on one side at a time or support springs to keep alignment; torque the self-locking nuts to manufacturer specs and inspect regularly for corrosion or bushing wear.

• Use jack stands and chock wheels before removing hardware
• Lubricate bolt shanks lightly and hand-start nuts before torqueing
• Recheck torque after a short break-in period and during routine inspections

Who this is for: This OZISENS equalizer and shackle kit is aimed at trailer owners, DIY mechanics, and repair shops that service tandem-axle trailers in the 3,500–5,200 lb range. If you need a full, matched set of equalizers, straps, bushings and fasteners to repair or refresh leaf spring linkages and prefer a ready-to-install package with corrosion-resistant finish, this kit covers common replacement needs and reduces parts scavenging.