The final drive is one of the most important parts of every heavy machinery; therefore, we must be aware of everything about Possible problems. So, here in this article, we will discuss the main fault of a final drive in Komatsu PC128 UU. The Komatsu PC128UU excavator is known for its compact power, reliability, and smooth operation in tight working areas. But like any hydraulic machine, its final drive assembly can develop problems over time, especially if the machine operates in demanding environments such as construction sites, quarries, or muddy terrains.
In this article, we’ll break down the main faults of the Komatsu PC128UU final drive, what causes them, how to detect early warning signs, and why Arena Hydraulic & Machinery is the trusted supplier and service provider for high-quality final drives and repairs across Australia, New Zealand, and neighbouring countries.
The final drive (also called a travel motor or travel drive) is the component that converts hydraulic pressure into mechanical torque, powering the excavator’s tracks.
In the Komatsu PC128UU, the final drive works as a hydraulic motor plus a planetary gear system, providing smooth movement, accurate control, and stability, whether the machine is working on steep slopes or confined urban areas.
When the final drive starts to fail, it directly affects the machine’s travel speed, power, and stability, often leading to costly downtime if not addressed quickly.
The most common fault in the final drive of the Komatsu PC128UU is oil leakage, often caused by worn or damaged seals inside the drive assembly.
This issue may seem minor at first, but if left untreated, it can quickly escalate into a major failure involving the bearings, planetary gears, and even the travel motor itself.
Common Causes of Oil Leakage
1. Worn floating seals due to contamination, heavy shock loads, or improper lubrication.
2. Blocked or restricted case drain line, causing excessive pressure inside the travel motor.
3. Overheated gear oil, which thins out and reduces its protective film strength.
4. Improper oil level or wrong oil type, leading to excessive wear on internal components.
5. Physical damage or misalignment after heavy impact or incorrect installation.
Catching the problem early can save thousands in repair costs. Here are key symptoms that indicate your Komatsu PC128UU final drive may be failing:
– Visible oil leaks around the sprocket or housing.
– Unusual noise, grinding, rumbling, or whining from the track area.
– Sluggish travel speed or one track moving slower than the other.
– Excessive heat on one side of the undercarriage.
– Metal shavings or dark oil during oil changes.
If any of these appear, stop the machine immediately and inspect the oil levels in both the gearbox and the hydraulic motor side. Operating with low or contaminated oil will cause severe internal damage in minutes.
At Arena Hydraulic & Machinery, our professional team specialises in repairing, rebuilding, and replacing Komatsu final drives, including the PC128UU model.
We don’t just replace parts, we diagnose the root cause of the failure using advanced test benches and quality inspection tools.
Here’s how our process works:
1. Comprehensive inspection and teardown
2. Professional cleaning and precision measurement
3. Replacement of critical components with high-grade parts
4. Bench testing before dispatch (pressure, flow, leakage, and noise levels)
5. 12-Month Warranty on all repairs and replacements
Arena Hydraulic & Machinery is one of the leading suppliers of final drives, swing motors, and hydraulic components for excavators from 1-ton to 100-ton applications.
Based in Australia, we proudly serve customers across Melbourne, Sydney, Brisbane, Perth, Adelaide, and throughout New Zealand, as well as nearby countries across the Asia-Pacific region.
What Sets Arena Apart:
– Extensive stock of new, OEM, and high-quality aftermarket final drives.
– Professional repair service for Komatsu PC128UU and other major brands including Caterpillar, Kobelco, Doosan, Hyundai, and Volvo.
– Fast turnaround time to minimise downtime.
– 12-month warranty on all drives and repairs.
– Australia-wide and international shipping with tracking and technical support.
Arena Hydraulic can supply or rebuild various Komatsu PC128UU final drive part numbers, including:
– 21Y-60-32111
– TZ601D200001K
– TZ600D1000-01
If you’re unsure which model fits your excavator, our team can help identify the exact part number using your machine’s serial number or photos of your old final drive.
Here are a few simple habits that will extend the life of your Komatsu final drive:
1. Check gear oil level weekly and replace every 1,000 hours or sooner in harsh conditions.
2. Inspect for leaks around the sprocket and inner cover.
3. Keep the undercarriage clean, especially around the track motors.
4. Use the correct oil grade recommended for your region’s temperature.
5. Monitor case-drain pressure to prevent seal blowout.
6. Service regularly with trusted professionals like Arena Hydraulic.
At Arena Hydraulic & Machinery, we believe every repair should restore your excavator to as-new condition, both in performance and reliability.
Our experienced technicians handle each job with precision, ensuring that when your Komatsu PC128UU leaves our workshop, it’s ready to perform in the toughest environments.
Whether you’re in Australia, New Zealand, or neighbouring regions, we’re committed to helping you get back to work fast , with tested, warranted, and high-quality final drives that you can trust.
If you suspect a fault in your Komatsu PC128UU final drive or need a replacement, contact Arena Hydraulic & Machinery today:
Head Office: Melbourne, Australia
Website: www.arenamachinery.au
Email: [email protected]
Phone: 03 8905 4303
From problem to power, that’s the Arena Hydraulic way.
As a leading supplier of hydraulic final drives in Australia, we're committed to providing our customers with the highest quality products and exceptional service. Our experts can help you find the perfect final drive for your application, ensuring you get the best value and performance.
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