Shop Talk Blog

Somebody's mad, and they have a right to be: just six months, maybe 400 hours, and their new final drive motor is acting up again. Did they buy junk?

Here at Texas Final Drive, we regularly open up final drive motors and the story of the failure is almost always written inside the motor. It’s not usually a manufacturing defect or a bad reman job. It’s often debris from the first failure that’s still living in the machine and ready to chew through a perfectly good replacement.

There’s a good chance that the drive isn’t the root cause. The system may have failed and got a fresh drive to devour.

What a Failed Final Drive Motor Leaves Behind

When a final drive motor fails, it never fails politely. We regularly see bearing races spall, pistons scuff, and the rotary group grind itself down. And all that metal goes somewhere. Fine particles may ride the case drain line straight back into the tank. Bigger particles hang out in the hoses, the cooler, the valve block, and the low spots in the hydraulic reservoir.

Here are a few other Shop Talk Blog posts you might find interesting:

• Case Drain Flow Testing: The One Test Most Operators Skip
  

• Why Rental Companies Trust Texas Final Drive 
  

• Don't Get Spooked by Your Final Drive!
  
  
  

If you've ever popped the hood on a 100°F+ afternoon and felt heat radiating off your machine before you even touched it, you already know what we're about to explain. That same kind of heat can affect your final drive motors, too. According to Brendan Casey in Machinery Lubrication, overheating ranks second on the list of the most common problems with hydraulic equipment.

We’re going to talk about what's happening inside your final drive motor when it's this hot, and what you can do about it.

Here are a few other Shop Talk Blog posts you might find interesting:

• Bobcat Final Drives: Leaking Seals and Crossrobbing

• 5 Gear Oil Mistakes That Can Kill Your Final Drive Motor

• Reman Final Drives in a Greener World

What Does Heat Do to a Final Drive Motor?

Here's the simple version of what's happening “under the hood”:hydraulic fluid is supposed to be thick enough to keep a protective film between all those moving metal parts inside your final drive (e.g., gears, bearings, the works). Think of it like the difference between spreading cold honey and warm honey. Cold honey holds its shape and coats things nicely. Warm honey runs thin and slides right off. Yourhydraulic fluid and gear oil do the same thing when the Texas heat gets into them: they thin out, and that protective film gets thinner right along with them.

On newer Bobcat models that share a common brake circuit, we've been seeing a failure pattern that starts small but takes out both final drives. And it might be affecting you! Read on to learn what it does and how to diagnose it on your equipment.

Most owners and operators don’t realize how important case drain flow is when evaluating and diagnosing a final drive motor. This test can tell you a great deal about what’s going on inside your final drive without having to open it up.

In this blog post, we take a look at case drain flow testing, including how to perform the test and how to interpret the results.

Internal Leakage

Internal leakage is designed to support lubrication and cooling of dynamic components (e.g., bearings, pistons, etc.). Now, this leakage never leaves the system. It will always be returned to the hydraulic reservoir, often via a low-pressure drain line. Internal leakage does not contribute to the work being done by the final drive motor, though.

There is a baseline case for the hydraulic motor drain flow on your machine. However, as wear increases internal clearances and internal seals wear out, the case drain flow increases. This directly reduces the final drive's volumetric efficiency.

Overheating is one of the earliest warning signs that something inside your final drive is going wrong. Before you hear grinding or experience a total failure, a steady rise in temperature often signals problems that you can catch early if you know what to look for.

In this Shop Talk Blog post, we’ll talk about what is considered too hot, then discuss the five key reasons why final drives overheat. We’ll wrap up with a quick review of what kind of damage overheating can cause and simple checks to address it.

Here are a few other Shop Talk Blog posts you might be interested in:

• Why Is My Skid Steer Acting Up?
• What Causes a Final Drive to Wear Out Prematurely
• Buying a Replacement Final Drive Motor
  

You probably maintain your tracks, filters, and attachments, but did you know that hydraulic fluid quietly destroys pumps and final drives when it’s neglected? Bad hydraulic fluid won’t fail overnight. Its effects are slow, causing excessive heat, accelerated wear, and power loss, until your equipment comes to a complete stop.

In this Shop Talk Blog post, we're looking at what it costs you to keep running your compact equipment on bad hydraulic fluid ... and the price is more than you budgeted for!

Here are a few other Shop Talk Blog posts you might find interesting:

• The Case Drain Filter: A Small Component That Prevents Big Trouble
• Why Rental Companies Trust Texas Final Drive
• 5 Warning Signs Your Final Drive Might Be Failing (And What to Do Next)

Just got your new or reman final drive motor and are having a little trouble identifying the ports? This Shop Talk Blog post is for you.

In this blog post, we’ll go over the four different categories of ports you can find on a final drive, what their purpose is, and how to identify them. For larger tonnage motors, we’ve also included a short video we made.

Here are some additional Texas Final Drive blog posts you might find helpful:

• Valve Blocks on Final Drive Hydraulic Motors
• The Ultimate Glossary of Terms About Hydraulic Motors
• What to Know Before You Order a Final Drive
  
  

You’re wrapping up a long day when you notice something small, like sluggish travel speed, uneven tracks, or a dark spot under your machine. It’s easy to ignore, right? And doesn’t seem to be a big deal. It can wait a few days. But far too often, a few days turn into weeks and months, and minor issues turn into significant problems fast. And keep this in mind: Every minute of downtime, every drop of leaking fluid, and every bit of neglect quietly eats into your bottom line.

In this Shop Talk Blog post, we’re going to look at five ways your mini excavator might be draining your wallet and what you can do about it.

Here are a few Shop Talk Blog posts you might find interesting:

• Entrained Air: Basic Facts You Need to Know
• Advanced Reman and Repair Techniques for Final Drives
• The 8 Most Common Issues with Hydraulic Cylinders on Compact Equipment

Ignoring Track Tension

If you don’t keep the tracks on your compact excavator at the proper tension, there’s going to be some problems. If you keep them too tight, you’re going to see excessive wear on critical components like the sprockets and rollers -- and your final drive motors. On the other hand, if the tracks aren’t kept tight enough, the tracks are more likely to slip and risk derailing in the middle of a job. 

Have you ever had a skid steer or excavator break down in the middle of a big job?

Hydraulic reliability isn’t just about uptime. It’s actually about keeping your equipment operational to avoid lost income, missed deadlines, and protecting the investment you've made in your equipment. 

In this Shop Talk Blog, we’re going to discuss how reliability is built, not something to take for granted. It starts with good habits, regular checks, and a strong maintenance culture.

Here are a few other Shop Talk Blog posts you might be interested in:

• The Facts about Large Skid Steer Loaders
• Do You Know These Facts About Timbco and TimberPro?
• Hydraulic Pump Failure

The Cost of Unreliable Hydraulics

A single hydraulic failure can have ripple effects on your compact equipment, including costly downtime, missed deadlines, and expensive repairs. And contamination and improper maintenance are among the top causes of failure for hydraulic equipment. Investing in the reliability of your equipment, on the other hand, pays for itself in fewer breakdowns, longer component life, and the ability to maintain the equipment's value. Let’s take a look at what your investment in reliability looks like.

It starts with noticing a small oil spot under your skid steer. You think, “I can deal with that later,” and before you know it, a week has turned into a month, and then, mid-job, your final drive motor seizes. Even the biggest leaks start small and always lead to expensive repairs or replacements.

Final drive leaks, whether it's your gear oil or hydraulic fluid, affect more than just fluid levels. If they aren’t addressed, they will lead to wasted money, lost productivity, and even totaled drive motors. 

In this Shop Talk Blog post, let’s break down why ignoring a final drive leak drains your wallet as well.

Here's a few Shop Talk Blog posts you might be interested in:

• Drive Sprockets and Track Drives
• Bobcat Mini Excavator Final Drive Motor Removal
• Why Is My Skid Steer Acting Up?