Product Introduction

This middle axle differential assembly is a heavy-duty, fully integrated unit, specifically engineered for multi-axle heavy-duty truck applications. It is constructed from high-strength cast iron and alloy steel, featuring a robust housing, precision-forged spiral bevel gears, and a complete inter-axle differential mechanism. The assembly includes the main reduction gear set, differential case, side gears, pinion gears, and an integrated differential lock mechanism, all pre-assembled and pre-adjusted to OE specifications. The gear teeth are precision-cut and carburized for exceptional wear resistance, while the housing is designed to withstand the high torque loads and dynamic stresses of multi-axle operation. Precision-machined mounting surfaces, oil passages, and a differential lock actuator ensure proper lubrication, alignment, and on-demand locking functionality, making it suitable for the demanding conditions of long-haul and heavy-load transportation.

Core Function

• Reduces the high-speed, low-torque input from the transmission to the low-speed, high-torque output required for driving the wheels.

• Distributes torque between the middle and rear axles, allowing them to rotate at different speeds to compensate for differences in tire wear and road conditions, preventing drivetrain binding.

• The integrated differential lock mechanism can be engaged to lock the middle and rear axles together, providing maximum traction in low-friction or off-road conditions.

Differential Of Middle Axle AZ9231320745 Sinotruk – Factory Direct Supply for Heavy-Duty Trucks

When your heavy-duty truck demands reliable torque distribution between both drive wheels, the Differential Of Middle Axle AZ9231320745 Sinotruk delivers exactly that. Engineered to handle extreme loads and harsh road conditions, this middle axle differential ensures smooth power splitting — so your fleet stays productive instead of sitting idle. At Mettlead, we supply this genuine-spec component directly from our factory in China, which means you get OEM-grade quality without the inflated middleman markup. Whether you’re managing a transport company or sourcing parts for aftermarket distribution, this differential is built to keep wheels turning.

Key Features and Benefits of Differential Of Middle Axle AZ9231320745

Choosing the right middle axle differential isn’t just about fit — it’s about long-term performance and cost efficiency. Here’s why procurement managers across Africa, the Middle East, and Southeast Asia trust this part number:

• Precise Torque Distribution: The differential evenly splits driving force to both rear wheels, allowing each wheel to rotate at different speeds during turns. This reduces tire wear and protects your drivetrain from unnecessary stress.
• Heavy-Duty Durability: Manufactured with high-strength alloy steel gears and heat-treated components, the AZ9231320745 withstands continuous heavy payloads and demanding operating conditions.
• OEM-Matching Specifications: Every dimension, gear ratio, and spline count matches the original Sinotruk factory standard. As a result, installation is straightforward with no modifications required.
• Strict Quality Control: Each unit undergoes rigorous inspection — including dimensional verification, hardness testing, and surface finish checks — before it leaves our facility.
• Cost-Effective Factory Pricing: Because we source directly from certified manufacturers in China, you eliminate unnecessary distribution layers. Consequently, your per-unit cost drops significantly on bulk orders.
• Extended Service Life: Premium lubrication compatibility and precision-ground gear teeth minimize friction losses, extending the operational lifespan of the entire middle axle assembly.

Application Scenarios – Where Does This Differential Perform?

The Differential Of Middle Axle AZ9231320745 Sinotruk is specifically designed for the middle axle assembly of Sinotruk heavy-duty vehicles. In essence, it serves as the heart of your truck’s rear drivetrain system. Here’s how it works in real-world conditions:

• Compatible Vehicle Range: This differential fits Sinotruk HOWO series heavy trucks and related models equipped with the middle axle configuration using part number AZ9231320745.
• Core Function: It acts as the middle axle differential, distributing driving power evenly to both left and right wheels while allowing speed variation between them.
• Straight-Line Hauling: During highway transport with full payload, the differential ensures equal torque delivery to both wheels, maintaining stable traction and minimizing drivetrain vibration.
• Cornering and Turning: When the vehicle navigates curves, the outer wheel needs to travel farther than the inner wheel. The differential accommodates this speed difference smoothly, preventing axle binding and excessive tire scrubbing.
• Mixed Terrain Operations: For trucks operating on construction sites or unpaved roads, this differential handles uneven traction conditions while protecting the axle shafts from torsional overload.

In short, whether your trucks haul cargo across long distances or navigate tight urban delivery routes, this middle axle differential adapts to every driving scenario your fleet encounters. For more Sinotruk components that complement this part, explore our full Sinotruk HOWO Truck Parts catalog.

Technical Specifications – Differential Of Middle Axle AZ9231320745

Accurate specifications matter when you’re verifying part compatibility. Below you’ll find the key parameters for this Sinotruk middle axle differential:

Need to browse additional rear axle components? Visit our dedicated Rear Axle Parts category page for a comprehensive selection.

OEM/ODM Capability – Custom Packaging and Flexible Solutions

At Mettlead, we understand that different markets have different requirements. That’s precisely why we offer flexible OEM and ODM services tailored to your business needs:

• White-Label Packaging: Want to sell under your own brand? We provide neutral or custom-branded packaging that meets your market positioning. Your customers see your brand, while we handle the manufacturing.
• Custom Packaging Design: From individual part boxes to pallet-level export packaging, we configure packaging to protect components during long-distance shipping and simplify your warehouse management.
• Batch Consistency: Whether you order 10 units or 1,000, every Differential Of Middle Axle AZ9231320745 meets the same dimensional and performance specifications. Our quality control process doesn’t compromise at scale.
• Technical Documentation Support: We can provide installation guides, fitment confirmation data, and product spec sheets to support your downstream sales team.
• Factory Visits Welcome: We encourage serious buyers to visit our facilities in China. Seeing our production lines and QC processes firsthand builds the trust that long-term partnerships require.

For a broader view of all Sinotruk truck parts we carry — from engine components to chassis parts — check out our comprehensive Sinotruk Truck Parts overview page.

Frequently Asked Questions – Differential Of Middle Axle AZ9231320745 Sinotruk

What exactly does the middle axle differential AZ9231320745 do?

Simply put, this differential sits in the middle axle housing and splits engine torque between the left and right drive wheels. It allows each wheel to spin at slightly different speeds — especially during turns — which prevents drivetrain binding and reduces mechanical stress on your axle shafts and tires.

Which truck models does this differential fit?

The AZ9231320745 is designed for Sinotruk HOWO heavy-duty trucks that use a tandem rear axle configuration. It specifically fits the middle axle position. However, we always recommend cross-referencing your truck’s VIN or existing part number to confirm compatibility before ordering.

How can I tell if my middle axle differential needs replacement?

Common signs include unusual whining or grinding noises from the middle axle area, uneven tire wear on rear wheels, vibrations at highway speed, or fluid leaks near the differential housing. If you notice any of these symptoms, the differential gears or bearings may be worn and due for replacement.

Is this an original Sinotruk part or an aftermarket replacement?

We supply OEM-equivalent aftermarket parts that match original Sinotruk specifications in material, dimensions, and performance. Every unit undergoes strict quality inspection to ensure it performs identically to the factory-installed component. Additionally, custom packaging options are available if you prefer branded presentation.

What’s the typical lifespan of this differential under normal conditions?

Under proper operating conditions — with regular oil changes and appropriate load management — this middle axle differential can last hundreds of thousands of kilometers. Lifespan ultimately depends on maintenance habits, payload levels, and road conditions. Using the correct gear oil grade and changing it at recommended intervals significantly extends service life.

Can I order a single unit, or is there a minimum quantity?

We accommodate both sample orders and bulk purchases. While our pricing becomes more competitive at higher volumes, we’re happy to supply smaller quantities so you can evaluate quality before committing to larger orders. Reach out to our team to discuss your specific requirements.

Ready to Source Your Differential Of Middle Axle AZ9231320745 Sinotruk?

Stop overpaying for middle axle differentials through multiple distribution layers. With Mettlead, you connect directly to the source — getting factory pricing, strict quality assurance, and reliable delivery timelines all in one place. Our team is standing by to provide quotes, confirm fitment details, and arrange fast shipping to your location.

Take the next step today: Contact Us now to request a competitive quote on the Differential Of Middle Axle AZ9231320745 Sinotruk. Whether you need one unit or a container load, we’ll put together a solution that works for your budget and timeline.