Product Introduction

This precision-forged gear is a core component of the transmission’s main shaft gear set, engineered to handle high torque loads and provide smooth, reliable engagement between third and fourth gears.

• Structure & Material:

• Material: High-strength alloy steel, precision-forged and heat-treated to achieve a hardened tooth surface and a tough, impact-resistant core.

• Design: A dual-profile helical gear with one set of teeth for 3rd gear and a second set for 4th gear, designed to mesh with the corresponding countershaft gears.

  • Performance:

• Transmits high torque loads during mid-speed driving and gear changes, ensuring smooth power delivery and precise engagement.

• The helical tooth design reduces noise, vibration, and harshness (NVH) while distributing load evenly across the gear teeth for increased durability.

  • Durability: The hardened steel construction and optimized tooth geometry withstand the high stress and impact of frequent gear changes and heavy-duty operation, ensuring long service life.

Core Function

1. Torque Transmission: Transmits engine torque from the countershaft to the main shaft in both 3rd and 4th gear ratios.

2. Gear Engagement: Slides along the main shaft to engage either 3rd or 4th gear, enabling smooth gear changes.

3. Noise Reduction: The helical tooth design minimizes gear noise and vibration, improving driving comfort.

3rd-4th Gear 215930300 ZF Gearbox – Premium Replacement Gear for Heavy-Duty Trucks

When your fleet depends on smooth, reliable gear transitions, every component inside the transmission counts. The 3rd-4th Gear 215930300 ZF Gearbox is a precision-engineered synchronizer gear that keeps power delivery seamless between third and fourth ratios. Sourced directly from Mettlead’s factory in China, this gear meets OEM dimensional standards while offering wholesale pricing that protects your margins. Whether you are restocking your warehouse or fulfilling an urgent customer order, this part is ready to ship and built to perform.

Key Features and Benefits of the 215930300 ZF Gearbox Gear

This isn’t just another gear sitting on a shelf. The 215930300 ZF Gearbox 3rd-4th Gear is manufactured under strict quality control protocols to ensure dimensional accuracy, surface hardness, and tooth profile consistency. Here’s what that means for your business:

• OEM-Grade Precision: Tooth geometry and spline tolerances match the original ZF specifications, ensuring a drop-in fit without machining or modification.
• Superior Material Composition: Forged from high-strength alloy steel, then case-hardened and heat-treated for exceptional wear resistance under heavy torque loads.
• Noise-Free Engagement: Precision grinding on the tooth flanks minimizes gear whine and ensures smooth 3rd-to-4th gear synchronization, reducing driver fatigue.
• Extended Service Life: The combination of surface hardness and core toughness means this gear outlasts inferior aftermarket alternatives, lowering warranty claims for distributors.
• Wholesale-Friendly Pricing: Factory-direct supply eliminates middlemen, giving agents and distributors room to maintain healthy profit margins even in competitive markets.
• White-Label Packaging Available: Build your own brand identity by requesting custom or neutral packaging on bulk orders.

In short, the 3rd-4th Gear 215930300 delivers the durability your customers expect and the cost structure your business needs. Explore our full range of transmission components on our ZF Gearbox Parts page.

Technical Specifications – 215930300 ZF 3rd-4th Gear

Need specifications for other gears or synchro assemblies? Browse our complete Gearbox Parts Category for a full catalog.

Application Scenarios – Where the 215930300 ZF 3rd-4th Gear Fits

The 3rd-4th Gear 215930300 ZF Gearbox is designed to work inside ZF-series manual and automated manual transmissions commonly found in Chinese heavy-duty truck platforms. Specifically, this gear is compatible with the following vehicle brands and models equipped with ZF gearboxes:

• SINOTRUK HOWO – A7, T7H, and TX series heavy tractor units
• SINOTRUK SITRAK – C7H and G7 long-haul models
• SHACMAN – X3000, F3000, and H3000 platforms
• FAW Jiefang – J6P and J7 series with ZF 16-speed transmissions
• DONGFENG – Kinland and Tianlong KX models using ZF gearbox variants
• FOTON Auman – EST and GTL heavy trucks

Whether your customers operate in mining haul routes, long-distance freight corridors, or heavy construction logistics, this gear handles the sustained torque and repetitive cycling those applications demand. Its hardened tooth surfaces resist pitting and micro-fatigue, even under aggressive driving patterns and high-temperature conditions.

OEM/ODM Capability – Customized Supply for Distributors

Mettlead understands that distributors and agents operate in diverse markets with unique branding and packaging requirements. That’s why we offer flexible OEM and ODM services for the 215930300 ZF Gearbox 3rd-4th Gear and all our transmission components:

• White-Label Packaging: Receive parts in neutral boxes ready for your own branding stickers or labels.
• Custom Packaging Design: We print your brand, logo, and part numbers directly onto the box for a fully branded unboxing experience.
• Custom Kitting: Bundle multiple gearbox parts into repair kits tailored to your market’s most common ZF overhaul jobs.
• Strict Quality Control: Every batch goes through dimensional inspection, hardness testing, and visual grading before packaging.
• Factory Visits Welcome: We invite serious wholesale partners to visit our production facility and quality labs in China for full transparency.

From small trial orders to container-load shipments, our logistics team ensures fast, reliable delivery with flexible, secure payment options that suit international trade.

Customer Case Study – African Distributor Scales with 215930300 ZF Gearbox Gear

A wholesale truck parts distributor based in East Africa was struggling with inconsistent quality from multiple suppliers of ZF transmission gears. Frequent returns and warranty claims on 3rd-4th gear failures were eroding their profit margins and damaging their reputation among workshop clients.

After switching to Mettlead as their primary source for the 3rd-4th Gear 215930300 ZF Gearbox, they experienced a measurable drop in return rates within the first six months. The hardened alloy gears consistently matched OEM fitment across HOWO and SHACMAN trucks—the most popular models in their region. Additionally, our white-label packaging allowed them to strengthen their own brand identity without investing in manufacturing.

Today, this partner orders quarterly in bulk and has expanded their catalog to include synchro rings, mainshaft gears, and countershaft assemblies from our ZF Gearbox Parts collection. Their feedback: “Mettlead’s 215930300 gear solved our quality problem and gave us pricing room to compete aggressively in the local market.”

Frequently Asked Questions – 3rd-4th Gear 215930300 ZF Gearbox

What is the exact function of the 215930300 gear inside the ZF gearbox?

The 215930300 is a synchronizer gear that facilitates smooth engagement between 3rd and 4th speed ratios. It works alongside the synchro ring and sliding sleeve to match shaft speeds during gear changes, preventing grinding and protecting other internal components from shock loads.

How do I confirm that the 215930300 ZF 3rd-4th Gear fits my specific truck model?

Cross-reference the part number 215930300 with your ZF gearbox model plate (usually stamped on the transmission housing). If you provide us with the gearbox serial number or truck chassis number, our technical team can verify compatibility before you place an order.

What causes premature failure of the 3rd-4th gear in ZF transmissions?

Common causes include contaminated transmission oil, worn synchro rings allowing metal-on-metal contact, driver habits such as forced shifting without full clutch engagement, and using non-hardened aftermarket gears that lack adequate surface treatment. Our 215930300 gear’s carburized case hardening directly addresses the last issue.

Can I order the 215930300 gear as part of a complete overhaul kit?

Yes. Mettlead can assemble custom overhaul kits that include the 3rd-4th gear 215930300, corresponding synchro rings, thrust washers, and seals. This is popular among distributors who serve repair workshops needing everything in one box.

What surface hardness should I expect from a quality 3rd-4th gear?

A properly heat-treated ZF 3rd-4th gear should have a surface (case) hardness of HRC 58–62 and a core hardness of HRC 30–38. This balance provides wear resistance on the tooth face while maintaining toughness to absorb shock without cracking. Every Mettlead gear is tested to confirm these values.

How should I store the 215930300 gear before installation?

Store in a dry, temperature-controlled environment, preferably in its original packaging. Apply a light coat of anti-rust oil if storage exceeds three months. Avoid stacking heavy items directly on gear teeth to prevent micro-deformation.

Ready to Stock the 215930300 ZF 3rd-4th Gear at Wholesale Prices?

Your customers need reliable ZF gearbox components, and your business needs a supplier that delivers consistent quality without inflated pricing. Mettlead bridges that gap with factory-direct manufacturing, rigorous inspection, and logistics built for international trade.

Take the next step today:

1. Tell us your required quantity and preferred packaging format.
2. Receive a competitive quotation within 24 hours.
3. Get your order dispatched with full tracking and secure payment processing.

Contact Us Now to request pricing on the 3rd-4th Gear 215930300 ZF Gearbox or any other transmission part in our catalog. Let’s build a supply partnership that keeps your shelves stocked and your customers coming back.