Product Introduction

• Structure: Precision closed-die forging from 20CrMnTi alloy steel, featuring an external involute tooth profile (32 teeth) and a keyed inner bore with an integrated needle roller bearing. The gear teeth undergo full carburizing, quenching, and precision grinding, achieving surface hardness HRC 58–62(anti-pitting/wear) and core hardness HRC 33–45 (anti-impact fracture). The needle bearing enables low-friction rotation relative to the shaft, while the keyway ensures a secure, non-slip torque transfer.

• Performance: The carburized tooth surface resists pitting and wear during long-term medium-to-high speed cruising, maintaining smooth meshing with the countershaft gear for over 60,000 hours of operation. The integrated needle bearing reduces friction between the gear and shaft, improving transmission efficiency and reducing heat generation. The keyed inner bore ensures a rigid, non-slip connection to the right output shaft, preventing slippage under medium torque loads.

Core Function

1. 4th gear power transmission: Meshes with the countershaft 4th gear to transmit torque from the countershaft to the right output shaft, supporting medium-to-high speed cruising.

2. Low-friction rotation: The integrated needle bearing enables low-resistance rotation of the gear relative to the shaft, improving transmission efficiency.

3. Fixed shaft engagement: The keyed inner bore locks the gear to the right output shaft, ensuring torque is transferred without slippage.

Output Shaft 4th Gear AZ2210030226 – SINOTRUK HW Series Gearbox Replacement Part

Precision-Engineered Output Shaft 4th Gear for SINOTRUK HW Gearbox

When your fleet depends on reliable power transmission, every single gear in the drivetrain matters. The Output Shaft 4th Gear AZ2210030226 is purpose-built for the SINOTRUK HW Series Gearbox, delivering the exact dimensional accuracy, surface hardness, and torque capacity that heavy-duty commercial vehicles demand. Whether you are restocking your warehouse or fulfilling urgent client orders, this genuine-spec replacement gear keeps transmissions shifting smoothly under the toughest operating conditions.

At Mettlead, we supply this gearbox component directly from our quality-certified production lines in China — meaning you get factory-gate pricing without sacrificing the precision your customers expect. As a result, your profit margins stay healthy while your end-users enjoy OE-level performance.

Key Features and Business Benefits

Superior Material and Heat Treatment

This output shaft 4th gear is forged from high-grade alloy steel, then case-hardened through carburizing and quenching processes. Consequently, the tooth surface achieves exceptional wear resistance while the gear core retains the toughness needed to absorb shock loads — a critical balance for heavy-truck gearboxes operating under frequent start-stop and heavy-load cycles.

OE-Matching Dimensional Precision

Every tooth profile, bore diameter, and spline specification on the AZ2210030226 matches the original SINOTRUK HW gearbox blueprint. Therefore, installation is straightforward with no modifications required, which reduces workshop time and eliminates costly fitting errors for your downstream customers.

Extended Service Life

Thanks to precision grinding and strict surface-finish control, this 4th gear operates with minimal friction and noise. In practical terms, that translates to longer intervals between gearbox overhauls — a selling point that helps your distributors win repeat business from fleet operators.

Wholesale-Ready Packaging and Pricing

Mettlead offers flexible MOQ arrangements, white-label packaging, and tiered volume pricing tailored to parts distributors and importers. In other words, you can brand the product as your own and scale your orders as demand grows.

Technical Specifications

Application Scenarios

The Output Shaft 4th Gear AZ2210030226 is specifically engineered as a transmission component for the SINOTRUK HW Series Gearbox. Below are the primary fitment and use-case scenarios:

• Compatible Vehicles: SINOTRUK HOWO A7, HOWO T7H, SITRAK C7H, and other heavy-duty trucks equipped with the HW-series manual transmission.
• Gearbox Models: HW19710, HW15710, HW19712 transmission assemblies where the 4th gear on the output shaft requires replacement due to wear, pitting, or tooth breakage.
• Typical Replacement Trigger: Gearbox noise in 4th gear, difficulty engaging 4th gear, or preventive overhaul during scheduled fleet maintenance.
• End-User Industries: Long-haul logistics, mining and quarrying haulage, construction material transport, and port container handling — all environments where the HW gearbox endures high torque and continuous cycling.

For a full catalog of compatible transmission parts, explore our Gearbox Parts Collection and SINOTRUK HOWO Gearbox Parts pages.

OEM/ODM Capabilities

Mettlead is more than a parts supplier — we are a manufacturing partner built to support your brand growth. Here is what we bring to the table:

• White-Label Production: We can produce and package the Output Shaft 4th Gear AZ2210030226 under your own brand identity, giving you full control over how the product appears to your customers.
• Custom Packaging: Choose from neutral export cartons, branded retail boxes, or bulk industrial packing — whatever best suits your distribution channel.
• Strict Quality Control: Every batch undergoes hardness testing, dimensional inspection, and surface-finish verification before shipment. We maintain full traceability records so you can audit quality at any time.
• Flexible Order Quantities: Whether you need a trial order of 50 pieces or a container-load replenishment, our production scheduling adapts to your inventory cycles.
• Factory Visits Welcome: We encourage prospective partners to visit our production facility in China to inspect processes firsthand and build long-term confidence in our capabilities.

Browse the complete range of SINOTRUK components on our SINOTRUK HOWO Truck Parts brand page.

Customer Case Study: Output Shaft 4th Gear AZ2210030226 Bulk Supply to East Africa

In early 2024, a truck parts distributor based in Nairobi approached Mettlead seeking a reliable source for SINOTRUK HW Series Gearbox components — particularly the Output Shaft 4th Gear AZ2210030226. Their previous supplier had delivered inconsistent hardness levels, leading to premature gear wear and warranty claims from their workshop customers.

After reviewing our production data and requesting a 100-piece sample lot, the distributor confirmed that our AZ2210030226 gears met OE hardness specs (HRC 60 average on tooth surfaces) and fit the HW19710 gearbox without dimensional deviation. Subsequently, they placed a standing quarterly order of 500 units under custom-branded packaging.

Within six months, their warranty return rate on 4th gear replacements dropped from 8% to under 1%. As a result, they expanded their Mettlead order list to include additional SINOTRUK HW gearbox output shaft gears and synchronizer assemblies. Today, they regard our Output Shaft 4th Gear AZ2210030226 as a benchmark product in their transmission parts catalog.

Frequently Asked Questions

What is the exact fitment for Output Shaft 4th Gear AZ2210030226?

This gear is designed exclusively for the SINOTRUK HW Series Gearbox output shaft, specifically at the 4th gear position. It fits HW19710, HW15710, and HW19712 transmission models commonly found in HOWO and SITRAK heavy trucks. Always confirm your gearbox model number before ordering to ensure correct fitment.

How does the AZ2210030226 gear achieve long service life in heavy-duty applications?

The combination of high-alloy steel substrate, precision carburizing to achieve HRC 58–63 surface hardness, and CNC-ground tooth profiles means the gear resists pitting, spalling, and abrasive wear — even under sustained high-torque conditions typical of mining or long-haul haulage applications.

Can I visually distinguish this gear from the original SINOTRUK part?

Our Output Shaft 4th Gear AZ2210030226 is manufactured to OE blueprints, so the tooth count, module, bore dimensions, and spline profile are identical to the factory original. The only visible difference may be the part marking, which we can customize to your preference under our white-label service.

What causes premature failure of the 4th gear on the HW gearbox output shaft?

Common failure causes include insufficient lubrication, contaminated gearbox oil, misaligned synchronizer sleeves, and operating the vehicle under sustained overloading. Installing a quality-controlled replacement like the AZ2210030226 restores proper meshing geometry, but addressing the root cause is equally important to prevent repeat failures.

Do you offer other output shaft gears for the SINOTRUK HW gearbox?

Yes. Mettlead supplies the complete output shaft gear set for HW-series transmissions, including 1st through 5th gears, reverse gears, and related synchronizer components. Visit our SINOTRUK HOWO Gearbox Parts page to view available part numbers.

Ready to Secure Your Wholesale Supply?

The Output Shaft 4th Gear AZ2210030226 for SINOTRUK HW Series Gearbox is in stock and ready for bulk dispatch. Whether you need 50 pieces for a trial or a full container for quarterly replenishment, Mettlead delivers competitive factory-direct pricing, rigorous quality assurance, and dependable lead times.

Take the next step:

• Request a detailed quotation with volume-based pricing.
• Ask about white-label packaging options for your brand.
• Inquire about combined shipments with other SINOTRUK gearbox parts.

Contact Us today to speak with our dedicated truck parts team. Let us build a supply partnership that keeps your inventory full and your customers satisfied.