Heavy-Duty 5-Blade 40" Semi-Elliptical Leaf Spring (70x10mm)

The Heavy-Duty 5-Blade 40" Semi-Elliptical Leaf Spring (70x10mm) is an industrial-grade, extended-span trailer suspension component engineered to provide robust payload support, superior shock absorption, and enhanced chassis stability for commercial freight trailers, touring caravans, heavy utility haulers, and agricultural transport chassis. Constructed with an extra-wide 70 mm blade width by 10 mm individual blade thickness arranged across a graduated 5-blade stack, this suspension assembly delivers high load-bearing capacity combined with the road-smoothing benefits of an extended 40-inch (~1,016 mm) mounting span.

The lengthened 40-inch arc distributes vertical roadway shocks and dynamic axle forces across a broader section of the trailer chassis, significantly reducing high-frequency vibrations and rebound bounce. The wide 70 mm footprint and heavy 10 mm individual leaves provide exceptional torsional and lateral stiffness, effectively suppressing trailer body roll, axle twist, and dynamic sway when carrying top-heavy equipment, machinery, or bulk cargo across corrugated gravel tracks, unpaved farm access roads, and long highway journeys. Manufactured from premium oil-quenched and tempered high-tensile spring steel, it preserves its arch profile and elasticity under demanding, high-mileage commercial duty cycles.

Key Features & Benefits:

• Heavy-Gauge 70x10mm Leaf Dimensions: Formed with extra-wide 70 mm leaves and 10 mm individual blade thickness to resist severe bending forces, lateral leaf splaying, and bottoming-out under heavy payloads.

• Extended 40-Inch Span (~1,016 mm): Longer arch length provides deeper, more progressive vertical deflection compared to standard shorter leaf packs, smoothing out roadway shock to protect chassis welds, fixtures, and cargo.

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

• 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 inside the slipper channel to allow unrestricted longitudinal travel under compression.

• Commercial-Grade Toughness: Engineered to endure high cyclic stresses, heavy brake torque, and prolonged transit over corrugated, gravel, and industrial terrain.

Ideal Applications:

• Commercial & Utility Trailers: Heavy running gear for single- and tandem-axle goods trailers, commercial flatbeds, and equipment haulers running wide-spring hanger setups.

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

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

• Plant & Machinery Transporters: Suspension for machinery carriers, contractor flatbeds, and mobile equipment platforms.

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

Product Specifications:

• Product Name: 5 Blade Spring 40" (70x10)

• Product Category: Suspension / Leaf Springs

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

• Number of Blades: 5 Blades

• Spring Length (Mounting Span): 40 Inches (~1,016 mm)

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

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

• Material: Quenched & Tempered High-Tensile Automotive Spring Steel

• Application Compatibility: Commercial Trailers, Caravans, Horseboxes, Utility & Agricultural Vehicles

• Condition: Brand New Heavy-Duty Commercial Vehicle Hardware