Heavy-Duty 5-Blade 40" Spring & Mounting Kit Combo (3,000kg Pair Capacity / 55mm Square Axle)

The Heavy-Duty 5-Blade 40" Spring & Mounting Kit Combo is an integrated commercial trailer suspension package engineered to deliver dependable payload support, lateral axle stability, and structural chassis integration for commercial transport trailers, agricultural wagons, heavy utility haulers, and touring caravan chassis. Rated for a combined axle capacity of 3,000 kg per pair (1,500 kg per individual spring assembly), this matched suspension kit is purpose-built to interface securely with 55 mm square solid or hollow-beam axles.

The core of the assembly is a robust 5-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 together with its dedicated chassis mounting hardware. 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 3,000kg Combined Rating (Per Pair): Delivers robust load-bearing capability supporting up to 1,500 kg per individual spring kit assembly across single- or tandem-axle trailer layouts.

• Matched 55mm Square Axle Fitment: Designed specifically to seat and anchor 55 mm square axle beams, ensuring accurate axle tracking, positive U-bolt clamping, and resistance against brake torque rotation.

• 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 heavy 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.

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

• Integrated Spring & Mounting Hardware: Supplied as an integrated assembly (1 spring plus matching mounting brackets), ensuring proper dimensional alignment, hanger clearances, and long-term 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.

Ideal Applications:

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

• Agricultural Implements & Farm Wagons: Heavy-duty running gear for field service carts, bulk wagons, and farm transport trailers operating over rough field terrain.

• Plant & Equipment Trailers: Medium-to-heavy suspension for machinery carriers, contractor flatbeds, and mobile equipment platforms.

• Heavy Touring Caravans & Campers: Extended-span suspension delivering a compliant, stable ride that cushions interior cabinetry, appliances, and onboard fittings against prolonged road vibration.

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

Product Specifications:

• Product Name: Spring & Mounting Kit 3,000kg

• Product Category: Suspension / Leaf Spring Kits

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

• Number of Blades: 5 Blades

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

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

• Load Rating: 3,000 kg per Pair (1,500 kg per Individual Spring Kit)

• Supported Axle Size: 55 mm Square Axle Beam

• Included Components: 1x 5-Blade 1,100mm Leaf Spring (70x10mm) plus dedicated Spring Mounting Kit Hardware

• 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, Caravans, Commercial Trailers, Utility Vehicles

• Condition: Brand New Heavy-Duty Commercial Vehicle Hardware