Heavy Duty HOWO Front Leaf Spring Assembly WG9725520076 / WG9725520078 Wholesale

Searching for precise OEM replacement HOWO Front Leaf Spring Assembly units (Part Numbers: WG9725520076 and WG9725520078) to supply SINOTRUK fleets, heavy commercial repair centers, or regional spare parts inventory? Engineered with high-tensile alloy spring steel, precision CNC hot eye rolling, and multi-layer dynamic arch control, our front suspension springs deliver superior steering stability, high load support, and long flexural fatigue life under severe transport conditions. Certified under strict ISO/TS 16949 quality management systems with European CE compliance, Haishuo is a direct OEM factory manufacturer supplying truck fleet operators, distributors, and spare parts wholesalers worldwide.

Product Overview

The HOWO Front Leaf Spring Assembly (OEM: WG9725520076 / WG9725520078) is a critical steer-axle suspension component specifically engineered for SINOTRUK HOWO heavy-duty commercial trucks. Mounted between the vehicle frame and front steering axle, the front leaf spring pack supports front engine dynamic weight, maintains correct wheel alignment, and absorbs front-end road vibration during long-haul freight and off-road transport.

Forged from high-tensile alloy spring steel, every front leaf spring pack manufactured by Haishuo features precision double rolled eyes with pre-installed high-durability rubber-metal or bronze bushings. Each unit undergoes computerized quenching and tempering, precision center-hole punching, and high-stress shot peening to prevent metal sagging, eye fracture, and premature flex failure. Built to withstand demanding haulage conditions across Southeast Asia, Africa, South America, and the Middle East, our springs match 100% of original factory specifications. We offer direct wholesale bulk manufacturing as well as custom engineering based on client drawings or samples.

Applicable Models

Key Features & Product Highlights

• Direct OEM Fitment (WG9725520076 / WG9725520078): Exact dimensional compatibility with original SINOTRUK HOWO front axle suspension brackets and shackle pins.

• Double Rolled Eye Construction: Precision CNC rolled main eyes engineered to tight inner diameter tolerances for smooth shackle rotation and reduced bushing wear.

• High-Tensile Forged Alloy Steel: Manufactured from premium alloy spring steel (60Si2Mn / 51CrV4 / SUP9) for high yield strength, impact toughness, and fracture resistance.

• Computerized Thermal Treatment & Shot Peening: Advanced quenching, tempering, and surface shot peening eliminate micro-fissures and maximize flexural cycle life for every HOWO Front Leaf Spring Assembly.

• Protective Industrial Coating: Finished with high-durability gray/black electrophoretic coating (E-coating) or heavy anti-rust primer to resist road salt spray, mud, and water corrosion.

• Heavy-Duty Alignment Clips & Hardware: Steel alignment clips prevent leaf splay and lateral displacement during tight cornering maneuvers.

Technical Specifications

Item	Specification
Product Name	Heavy Duty HOWO Front Leaf Spring Assembly
Primary Keyword	HOWO Front Leaf Spring Assembly
OEM Reference Numbers	WG9725520076 / WG9725520078 / AZ9725520076
Target Vehicle Brand	SINOTRUK (China National Heavy Duty Truck Group)
Suspension Position	Front Steer Axle Suspension
Eye Configuration	Double Rolled Pivot Eyes with Rubber-Steel or Bronze Bushings
Material Grade	Premium Alloy Spring Steel (60Si2Mn / 51CrV4 / SUP9)
Manufacturing Process	CNC Shearing, Hot Eye Rolling, Heat Treatment, Shot Peening, E-Coating
Surface Finish	Gray / Black Industrial Anti-Rust Coating (E-Coating)
Quality Certification	ISO/TS 16949 Certified, CE Compliance, SGS Tested

Vehicle Application & OEM Compatibility

Our HOWO Front Leaf Spring Assembly (WG9725520076 / WG9725520078) is specifically engineered for high-tonnage SINOTRUK commercial trucks:

• SINOTRUK HOWO 7 Series: HOWO 336, HOWO 371, HOWO 380, HOWO 420 Heavy Duty Dump Trucks & Tractor Head Rigs (4×2, 6×4, 8×4).

• SINOTRUK HOWO A7 Series: HOWO A7 Heavy Duty Cargo Trucks & Tipper Chassis.

• SINOTRUK HOWO TX & NX Series: Modern Generation Construction & Logistics Transport Rigs.

• Specialized Heavy Vehicles: Compatible with HOWO concrete mixer trucks, water tankers, and heavy mining support trucks.

(Because front leaf spring leaf counts can vary between standard highway logistics and heavy mining configurations, please confirm your exact OEM part numbers or physical dimensions with our technical team.)

Common Signs Your HOWO Front Spring Needs Replacement

Routine inspection of front steer axle leaf springs is essential to ensure steering control and vehicle safety. Replace your HOWO Front Leaf Spring Assembly if you observe the following symptoms:

• Front-End Leaning or Uneven Stance: The front bumper sitting lower on one side due to lost arch height or leaf fatigue.

• Steering Instability or Front-End Wandering: Difficulty maintaining straight-line tracking caused by worn main eye bushings or loose center pins.

• Visible Leaf Fractures or Snapped Leaves: Cracks appearing around the center pin hole or main rolled eye zone.

• Unusual Front Tire Tread Wear: Rapid or uneven front tire wear resulting from altered front axle caster and camber angles.

• Heavy Metallic Clunking Over Bumps: Metal-on-metal contact caused by broken alignment clips or worn shackle bushings.

Technical Inspection & Quality Control

Every HOWO Front Leaf Spring Assembly undergoes strict multi-stage quality control checks matching original equipment manufacturer standards:

• 3D Geometry & Arch Verification: Precision laser measurement of total eye-to-eye span length, free arch height, blade thickness profile, and center pin positioning.

• Hydraulic Load & Deflection Testing: Verified on high-tonnage dynamic hydraulic presses to guarantee precise spring rate and dynamic rebound under max front axle loads.

• Metallurgical & Hardness Testing: Hardness testing verifies uniform heat treatment grain structure and dynamic tensile resilience across all leaves.

Manufacturing Process

1. Raw Steel Inspection: High-tensile alloy spring steel flat bars undergo chemical composition analysis and tensile strength testing.

2. CNC Cutting & Hot Eye Rolling: Precision shearing, end tapering, CNC main eye forming, and center bolt hole punching.

3. Quenching, Tempering & Shot Peening: Computerized thermal treatment maximizes structural toughness, followed by shot peening to prevent fatigue micro-cracks.

4. Coating & Bushing Fitment: Leaves receive a durable gray/black E-coating before precision hydraulic pressing of eye bushings.

5. Final Inspection & Packaging: 100% visual, dimensional, and dynamic load-deflection checks prior to export shipping.

Packaging & Export Shipping

• Anti-Rust Protection: Treated with protective rust-inhibiting coating and wrapped in heavy moisture-proof plastic film.

• Non-Fumigation Plywood Pallets: Secured on heavy-duty non-fumigation export pallets for rapid customs clearance at destination ports.

• High-Tensile Steel Strapping: Bound firmly with heavy steel bands and protective corner guards to guarantee zero shifting during ocean transit.

• Container Loading Optimization: Customized container space utilization plans to maximize loading capacity in 20ft and 40ft HQ containers.

OEM & Custom Wholesale Manufacturing Services

We provide comprehensive OEM/ODM production capabilities for spare parts importers, fleet managers, and SINOTRUK repair centers:

• Direct OEM matching for part numbers WG9725520076, WG9725520078, and related variants.

• Custom leaf counts, leaf thickness profile, arch height, and bushing material choices.

• Private labeling, laser OEM part number engraving, and customized export packaging.

Frequently Asked Questions (FAQ)

Q1: What is the difference between WG9725520076 and WG9725520078?

A: In SINOTRUK HOWO cataloging, WG9725520076 and WG9725520078 usually represent left/right pairing or standard vs. heavy-duty front spring options for steer axles. We manufacture both specs to exact OEM tolerances.

Q2: Does this front spring assembly come with bushings installed?

A: Yes! Our HOWO Front Leaf Spring Assembly comes with pre-installed heavy-duty rubber-metal or steel bushings ready for direct installation on shackle mounts.

Q3: What steel grades do you use for HOWO front springs?

A: We use premium high-tensile alloy spring steels such as 60Si2Mn, 51CrV4, and SUP9 to guarantee high yield strength and long flexural fatigue life.

Q4: Do you supply sample units for fitment testing?

A: Yes, sample units are available for distributors and fleet owners to verify eye-to-eye dimensions, arch height, and shackle fitment prior to bulk container orders.

Q5: What is the standard production lead time for bulk export orders?

A: Standard manufacturing lead time typically ranges from 15 to 25 days depending on total order volume, customized tooling needs, and surface finish choices.

Request a Quote

Keep your SINOTRUK HOWO fleets running safely with OEM-grade front suspension components! Contact our technical sales team today to request a competitive wholesale quote for our ISO/TS 16949 certified HOWO Front Leaf Spring Assembly (WG9725520076 / WG9725520078) products!