At Arena Hydraulic and Machinery, we’ve repaired hundreds of final drives that failed for one simple reason: a damaged or neglected floating seal. In compact and mini excavators (1 to 10 tonnes), which have limited oil capacity, a leaking seal can rapidly lead to catastrophic failure. What starts as a minor oil seepage can quickly escalate into significant damage if ignored.
Also known as a duo cone seal, the floating seal is a critical component inside your final drive. It does two essential jobs:
When this seal wears out, or when one of its O-rings becomes flattened or brittle due to age, the seal can no longer hold pressure. Sometimes, external objects like small rocks or metal shavings can also damage the sealing surface.
The result?
You get oil leaks, and worse, dust, water, and grit enter the drive. With every rotation, the internal components begin to grind and overheat, ultimately leading to the complete failure of the entire final drive.
Just take a look at these actual cases from our workshop:
This final drive had shown signs of leakage for weeks, but the operator had not noticed. Without oil, the gears inside were grinding dry, leading to corrosion and failure.
Here’s the culprit: corroded and compromised floating seals. These rings lost their tension, leading to leaks and exposure of the gearbox.
Once water and debris entered, it was only a matter of time. The gear teeth show clear signs of abrasion and rust. This drive was beyond repair and had to be replaced.
Machines under 10 tonnes are especially vulnerable because their gearbox holds less oil. A small leak equals a significant risk. Even just 100ml of oil loss can expose critical components. Unfortunately, in many cases, operators don’t notice leakage until the machine starts making noises or stops moving entirely.
It’s not about bad luck. It’s about missed warning signs.
Here’s the good news: a faulty floating seal is easy and affordable to replace if caught early.
If you’re mechanically skilled, you can buy a quality duo cone seal from Arena Hydraulic and replace it yourself. If you’re unsure, we recommend removing the drive and having it inspected by our technicians.
If the drive is still healthy inside, we’ll replace the seal, top up the oil, and get you back on the job quickly.
By acting early, you’re not just protecting your machinery, you’re saving thousands in repairs and lost productivity.
And if your drive is already damaged, don’t worry, we offer trade-in options. We’ll assess your old unit, purchase it if repair isn’t viable, and offer you a brand-new or rebuilt final drive at a competitive price.
With over 30 years of experience, we’ve seen it all. That’s why we carry a full range of:
Our team of professionals is here to help you make informed, cost-effective decisions about your equipment so you get the maximum life out of your machine.
Don’t let a small seal turn into a big problem.
If you suspect a leak or notice grease and oil around your track motor, act now—and protect your final drive before it’s too late.
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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