OZISENS Trailer Axle Equalizer Kit 312L for 3,500–5,200 lb Tandem Trailers — Hardened Steel Black-Oxide Complete Shackle Set

OZISENS 312L trailer axle equalizer and shackle kit is a complete replacement set engineered to service tandem-axle trailers rated between 3,500 and 5,200 pounds.

This kit bundles the equalizers, shackle straps, bushings, bolts and nuts needed to refresh or repair double-eye spring tandem suspension systems. Built from hardened steel with a black-oxidized finish, the components resist corrosion and hold alignment under towing loads. The kit is sized for common light- to medium-duty trailer axles, and includes clear part counts so you can verify fitment before installation.

Will this kit fit my trailer axle and springs?

Confirm fit by matching your trailer’s axle rating and the physical dimensions listed with the kit. It’s intended for tandem-axle setups using double-eye leaf springs and axles rated from 3,500 to 5,200 lb.

• Designed for 3,500–5,200 lb axle capacities.
• Includes two 7-3/4" equalizers for tandem suspensions.
• Shackle straps measure 4.4" with 3-1/8" (3.12") hole spacing.
• Check existing spring eye and bolt diameters before ordering.

What hardware and dimensions come with the set?

The package contains every fastener and bushing required to replace the equalizer and shackle assembly, reducing the need to source extra parts.

• 2 x 7-3/4" EQ-E1 equalizers.
• 8 x 4.4" shackle straps with 3-1/8" hole spacing.
• 14 x bolts at 3-3/8" length and matching 9/16"-18 self-locking nuts.
• 14 x nylon bushings with 9/16" I.D. and 11/16" O.D.

How durable and corrosion-resistant are the parts?

Components are manufactured from hard-wearing steel with a protective surface finish to slow rust and maintain structural integrity under load. The design resists bending and abrasion common in trailer service environments.

• Hardened steel construction for strength and wear resistance.
• Black oxidized and painted surface to reduce corrosion risk.
• Nylon bushings to reduce metal-on-metal wear.
• Self-locking nuts help prevent loosening from vibration.

What should I expect during installation?

Installation is similar to other double-eye leaf spring equalizer kits; basic tools and standard mechanical experience are usually sufficient. Because the kit includes all bolts, nuts and bushings, you only need to confirm torque specs and alignment for your trailer model.

• Supplied bolts and nuts cover both equalizer and shackle mounting points.
• Replace old bushings with supplied nylon bushings for smoother pivoting.
• Verify torque values from the trailer manufacturer before final tightening.
• Inspect spring eyes and perches for wear while replacing the kit.

Who is this for: This OZISENS 312L equalizer and shackle kit is for trailer owners, repair shops, and fleet maintenance teams who need a full replacement kit for tandem-axle trailers between 3,500 and 5,200 lb. It’s suited to DIYers comfortable with suspension work and professionals seeking a complete parts set — including equalizers, shackle straps, nylon bushings, bolts and locking nuts — that reduces sourcing time and helps restore proper suspension articulation.