Heavy-Duty 8-Blade 40" Spring & Mounting Kit Combo (4,000kg Pair Capacity / 60mm Square Axle)

The Heavy-Duty 8-Blade 40" Spring & Mounting Kit Combo is a complete, single-side commercial trailer suspension package engineered to deliver dependable payload support, lateral axle stability, and structural chassis integration for heavy transport trailers, commercial flatbeds, agricultural wagons, and equipment carriers. Rated for a combined axle capacity of 4,000 kg per pair (2,000 kg per individual spring assembly), this integrated suspension kit is purpose-built to interface securely with 60 mm square solid or hollow-beam axles.

The core of the assembly is an extra-heavy-duty 8-blade semi-elliptical leaf spring spanning 1,100 mm (~40 inches), manufactured with heavy-duty 70 mm wide by 10 mm thick individual heat-treated spring steel leaves. Supplied as a complete setup per corner/side, the assembly includes the leaf spring along with its dedicated chassis-mounting brackets and axle clamping hardware (weld-on front hanger, weld-on rear slipper assembly, 5-hole clamping tie plate, and matching square U-bolts). This matched configuration ensures exact bracket fitment, proper pin clearances, and unrestricted slipper travel, eliminating component mismatching while simplifying chassis fabrication and suspension overhaul.

Key Features & Benefits:

• High-Capacity 4,000kg Combined Rating (Per Pair): Delivers robust load-bearing capability supporting up to 2,000 kg per individual spring kit assembly across single- or tandem-axle trailer layouts.

• Matched 60mm Square Axle Fitment: Designed specifically to seat and anchor 60 mm square axle beams, ensuring positive axle location, maximum clamping contact, and resistance against axle twist under heavy braking torque.

• Heavy-Gauge 70x10mm Blade Dimensions: Extra-wide 70 mm leaves with 10 mm individual blade thickness resist severe vertical bending forces, lateral leaf splaying, and premature bottoming-out under demanding payloads.

• Extended 1,100mm Span (~40 Inches): Longer arch length provides deeper, more progressive vertical deflection than standard shorter springs, smoothing out roadway shock to protect chassis welds and sensitive cargo.

• 8-Blade Progressive Multi-Leaf Stack: Dense 8-leaf graduated architecture absorbs roadway shock and cyclic impacts progressively, shielding chassis crossmembers and axle beams from structural stress fatigue.

• Complete Corner Kit Integration: Comes bundled with both chassis-attachment brackets (forward eye hanger and rear slipper guide) and axle-tie components (square U-bolts and 5-hole clamping plate), ensuring proper installation fit and wear characteristics.

• High Torsional & Roll Stability: The wide 70 mm leaf footprint maximizes lateral stability to minimize trailer body roll, dynamic swaying, and shifting in high-center-of-gravity loads.

• Quenched & Tempered Spring Alloy Steel: Built from automotive-grade heat-treated spring steel to combat fatigue failure, leaf sagging, and loss of arch height over long working lifetimes.

• Standard Eye-to-Slipper Orientation: Forward rolled and bushed spring eye anchors securely into the front chassis hanger bracket for positive axle tracking, while the rear slipper tail glides freely to allow unrestricted longitudinal travel under compression.

Kit Contents (Per Spring Assembly):

• 1x 8-Blade Leaf Spring: 1,100 mm (~40") Semi-Elliptical Leaf Spring (70 mm x 10 mm)

• 1x Front Hanger Bracket: Heavy-duty weld-on 70 mm front spring eye hanger bracket

• 1x Rear Slipper Assembly: Heavy-duty weld-on 70 mm rear slipper hanger assembly

• 1x 5-Hole Clamping Plate: Heavy-gauge tie plate sized for 60 mm square axle clamping

• 2x Square U-Bolts with Hex Nuts: High-tensile square-bend U-bolts sized for 60 mm square axles

Ideal Applications:

• Commercial & Freight Trailers: Running gear for single- and tandem-axle goods trailers, commercial flatbeds, and enclosed transport haulers.

• Agricultural Implements & Bulk Wagons: Heavy-duty running gear for grain carts, water bowsers, fertilizer spreaders, and farm transport trailers operating over rough field terrain.

• Plant & Machinery Transporters: Medium-to-heavy suspension for mini-excavator carriers, compaction equipment trailers, and contractor plant flatbeds.

• Livestock Transporters & Heavy Horseboxes: Running gear engineered to handle dynamic animal movement while reducing body roll and trailer sway.

Product Specifications:

• Product Name: Spring Kit 4,000kg

• Product Category: Suspension / Leaf Spring Kits

• Spring Type: Heavy-Duty Semi-Elliptical Leaf Spring (Eye-and-Slipper Design)

• Number of Blades: 8 Blades

• Spring Length (Overall Span): 1,100 mm (~40 Inches)

• Blade Dimensions: 70 mm Width x 10 mm Blade Thickness

• Load Rating: 4,000 kg per Pair (2,000 kg per Individual Spring Kit)

• Supported Axle Size: 60 mm Square Axle Beam

• Included Components: 1x 8-Blade 1,100mm Leaf Spring (70x10mm), 1x Front Hanger Bracket, 1x Rear Slipper Assembly, 1x 5-Hole Plate, 2x Square U-Bolts with Nuts

• Installation Orientation: Front Spring Eye mounts towards the front of the trailer

• Material: Quenched & Tempered High-Tensile Automotive Spring Steel / Weldable Structural Steel Brackets

• Application Compatibility: Agricultural Implements, Heavy Commercial Trailers, Plant & Utility Vehicles

• Condition: Brand New Heavy-Duty Commercial Vehicle Hardware