31NB-40030 Travel Motor Assy for Hyundai R450-7 R480-9 R500-7 R520-9 | Heavy-Duty Mining Final Drive

The 31NB-40030 Travel Motor and Final Drive Assembly is the high-torque propulsion powerhouse engineered for Hyundai Robex (R) series heavy excavators. Specifically designed for the R450-7, R480-9, R500-7, and R520-9 models, this unit is built to manage the extreme tractive demands of the 45 to 52-ton class. It combines a high-displacement axial piston motor with a rugged three-stage planetary reduction gearbox to ensure your machine can navigate steep pit gradients and heavy overburden with ease.

Maximum Drawbar Pull for Massive Production In the 50-ton class, mobility is everything. The Hyundai R480-9 and R520-9 are built for high-production quarrying and mining. The 31NB-40030 final drive is the critical mechanical link that translates hydraulic pressure into the massive torque required to move these giants.

If your machine is feeling sluggish on slopes or exhibiting "tracking drift" (veering to one side), your travel motor is likely experiencing internal bypass. Our premium replacement units are engineered to handle the high duty cycles of large-scale earthmoving. Featuring precision-ground sun gears and high-load bearings, this assembly restores the factory-standard track synchronization and breakout force, ensuring your machine stays productive in the toughest pit conditions.

• North America & Australia: Built for the 24/7 "Uptime" requirements of the Mining and Aggregate sectors. These units are fully compatible with high-pressure hydraulic systems and heavy-duty undercarriage loads.

• CIS Regions & Northern Europe: Engineered with metallurgical properties that maintain structural toughness in extreme sub-zero temperatures, preventing housing cracks during high-torque cold starts.

• Southeast Asia & Africa: Optimized with "Mining-Grade" floating seals to prevent the ingress of abrasive volcanic dust, tropical mud, and mineral-heavy water common in open-pit operations.

The Case Drain Warning: For large excavators like the R520-9, case drain backpressure is the "silent killer." Before installing your new 31NB-40030, you must check your case drain line. A blocked line or dirty filter will blow the main shaft seal of your new motor within the first hour of operation.

• Oil Sampling (S.O.S.): For a drive of this size, regular oil analysis is vital. Watch for spikes in iron or copper levels; catching bearing spalling early can save the entire planetary gear set from catastrophic failure.

• Magnetic Plug Inspection: Clean and inspect the magnetic drain plugs at every 500-hour service. Fine gray "fuzz" is normal wear; distinct metal flakes mean it's time for an internal inspection.

• Sprocket Bolt Replacement: Due to the massive torque, sprocket bolts can stretch. Never reuse old bolts. Always use new Grade 12.9 bolts and a high-strength thread locker to prevent the sprocket from working loose.

Guangzhou Tieqi Construction Machinery Co., Ltd. (IRON CAVALRY) is strategically located in Guangzhou's Huangpu District, approximately an hour from Baiyun International Airport. We have been a dedicated specialist in engineering machinery hydraulics for nearly 15 years.

Driven by our core values of "Pragmatism and Progress," we are committed to delivering practical solutions and upholding our responsibilities. This principle-driven approach defines all our operations and client partnerships.

In China's excavator hydraulic assembly sector, our efficient execution and rigorous approach to manufacturing every product to meet over 95% of original performance specifications have built widespread trust. This has made us a destination for industry peers and clients seeking knowledge and reliable supply.

Our capability is backed by a ready inventory of over 500 assembly types, providing access to more than 6,000 different parts. Hydraulic pump, control valve, travel, and swing assemblies are our core products, with a distinct advantage in large mining excavator components and hard-to-find items.

Our 4,000-square-meter factory in Guangzhou is equipped for professional manufacturing, precision assembly, rigorous testing, and quality certification, ensuring reliable performance and timely delivery for every order.

For large items, we use sturdy plywood crates secured with metal fasteners for added stability. Inside, the products are cushioned with bubble wrap and secured with wooden braces, while special attention is given to protecting vulnerable parts. Externally, the crates are reinforced with high-strength PET plastic strapping and wrapped in highly waterproof black film.

• One-stop solution provider for all your hydraulic component needs
• High-quality products at competitive prices
• Exceptional customer service that makes you feel at home
• Large inventory, short delivery times, and long warranty periods
• Professional expertise with accurate part number identification for excavator components