40mm Square Spring Mounting Kit (44.5mm Spring Width)

The 40mm Square Spring Mounting Kit is a complete single-side trailer suspension hardware installation package engineered to secure 44.5 mm wide semi-elliptical leaf springs directly to 40 mm square solid or hollow-beam trailer axles. Designed for light-to-medium utility trailers, luggage trailers, camping trailers, and lightweight touring caravans, this matched assembly supplies all vital chassis-mounting brackets and axle clamping hardware required to mount one leaf spring corner securely to the trailer chassis and axle beam.

Fabricated from heavy-gauge, weldable structural steel and high-tensile threaded fasteners, the hardware configuration provides positive axle location, resists axle rotational twist under heavy braking torque, and evenly distributes dynamic road impacts into the trailer subframe. The kit includes square-bend U-bolts contoured to fit flush over 40 mm square axle profiles, paired with a reinforced 5-hole U-bolt clamping plate, a weld-on front eye hanger bracket, and a weld-on rear slipper bracket to allow smooth longitudinal spring deflection under load.

Key Features & Benefits:

• Engineered for 40mm Square Axle Beams: Square-bend U-bolts sit flush across 40 mm square solid or hollow axle tubing, providing maximum surface contact and preventing axle slip or twisting under braking forces.

• Matched to 44.5mm Wide Leaf Springs: Hanger bracket, rear slipper channel, and U-bolt spacing are precisely calibrated for standard 44.5 mm (1-3/4") spring blades, eliminating lateral binding and inter-leaf friction.

• Heavy-Duty 5-Hole Clamping Plate: Thick stamped steel clamping plate provides uniform pressure distribution across the spring pack and center locating bolt, preventing bolt shear and leaf shifting.

• Integrated Chassis & Axle Mounting Package: Combines both chassis-attachment brackets (forward eye hanger and rear slipper) and axle-tie components (square U-bolts, plate, nuts) into a single matched set per spring.

• Weldable Structural Steel Brackets: Uncoated steel hanger and slipper brackets are ready for immediate welding to trailer chassis runners, crossmembers, or subframe rails.

• High-Tensile Fasteners: Precision-threaded U-bolts and heavy-duty hex nuts maintain secure clamping torque against constant vibration and repetitive dynamic impacts.

Kit Contents (Per Spring Assembly):

• 1x U-Bolt Clamping Plate: Heavy-gauge 5-hole top/bottom tie plate

• 2x Square U-Bolts with Hex Nuts: High-tensile square-bend U-bolts sized for 40 mm square axles

• 1x Front Hanger Bracket: Weld-on forward spring eye mounting bracket

• 1x Rear Slipper Bracket: Weld-on rear slipper guide channel bracket

Ideal Applications:

• Light Utility & Box Trailers: Single- and tandem-axle general goods trailers and garden waste runabouts built on 40 mm square axles.

• Camping & Luggage Trailers: Lightweight off-road and on-road camping trailers utilizing 44.5 mm wide slipper leaf springs.

• Light Commercial Haulers: Maintenance carts, mobile generator trailers, and tradesman utility platforms.

• Suspension Overhauls & Rebuilds: Complete replacement hardware assembly for refitting worn hangers, damaged U-bolts, or bent clamping plates.

Product Specifications:

• Product Name: 40mm Square Spring Mounting Kit

• Product Category: Suspension / Spring Mounting Kits

• Supported Axle Profile: 40 mm Square (Solid or Hollow Beam)

• Supported Spring Width: 44.5 mm (1-3/4") Wide Leaf Springs

• Configuration: Single Spring Corner Kit (1 Side)

• Chassis Attachment: Weld-on Front Hanger and Rear Slipper Brackets

• Material: Heavy-Gauge Structural Steel Plate and High-Tensile Fasteners

• Application Compatibility: Utility Trailers, Caravans, Luggage Campers, Commercial Trailers

• Condition: Brand New Commercial Vehicle Hardware