If you own an excavator, skid steer, or other piece of construction equipment, you know the importance of a final drive to peak performance for your equipment. A final drive issue can lead to costly downtime for your crew when integrated hydraulic motors fail and cause the machine to lose mobility.
In this post, we’ll share what to look for to catch potential final drive problems early so you can take action early.
How Do Final Drives Work in Construction Equipment?
A final drive is the main power source for moving tracked construction equipment like mini excavators, skid steers, and compact track loaders. This component transfers hydraulic energy from the engine to the tracks, allowing for efficient movement and turning.
Depending on the machine, the size and shape of your final drive can vary, but it’s important to know what to look for if you suspect a problem.
Common Final Drive Issues and How to Recognize Them
If you suspect issues with a final drive, seek immediate attention from a knowledgeable service technician. Our staff at Prime Source can help you schedule service for your equipment and help you order the final drive replacement parts you need.
Here are a few common issues related to final drives.
Oil Leaks
If you notice an oil leak underneath the gearbox cover plate, it typically indicates a cover distortion or an accumulation of pressure inside the gearbox. These issues can eventually cause the gears to wear out or the gearbox to rip apart.
The ring gear is another area where oil leaks can occur. A damaged or worn seal is usually the culprit; you can fix the problem quickly by replacing it.
Too Much Oil
Working gears can sometimes generate excess heat, causing the oil to expand and loosen the seals. The result can be leaks or a potentially damaging buildup of hydraulic pressure.
Assuming you’ve maintained the appropriate oil level, the cause could be worn-out bearings between the gearbox and the final drive motor. You can correct this issue with a simple bearing or seal replacement.
Unusual or Excessive Noise
While you’re probably accustomed to the loud noises, an unfamiliar grinding or clunking sound could signal final drive trouble. Possible causes include an insufficient oil level in the gearbox, worn gears or bearings, or impurities in the oil. A lack of preventive maintenance is usually a contributing factor in each of these situations.
Idling
Is the final drive’s motor idling when it shouldn’t? The cause could be a broken motor shaft or a worn friction plate that you’ll need to replace.
Difficulty Navigating Terrain
Your excavator should be able to traverse rough ground without much trouble. If your equipment has difficulties moving over rugged turf, it could indicate a final drive-related issue, such as low hydraulic pressure in the hydro motor. Other possible causes include a worn-out travel motor or gearbox.
No Gearbox Motion
In some cases, the gearbox won’t move even though the motor appears to function correctly. The most common cause is a broken motor shaft, which requires replacing the shaft and the first drive gear. Other possible culprits are a broken drive shaft or a sun gear.
Final Drive Maintenance Basics for Construction Equipment
Timely preventive maintenance on all your heavy equipment will help keep final drives in prime working condition, extend their life span, and significantly reduce the failure risk.
Your service regimen should include several standard procedures, including:
Checking Gear Oil
Oil is essential for lubricating moving parts and preventing damaging friction, so regularly checking it is a maintenance practice you shouldn’t overlook. As a best practice, you should monitor your final drive’s gear oil level at least once per month or every 100 service hours.
At a minimum, an annual oil change is also necessary. Your equipment may require a shorter interval between changes in heavy-use conditions.
Inspecting Case Drain Filters
Some excavator and mini-excavator models have case drain filters to reduce the risk of cross-contamination. A clean filter that doesn’t need to be changed will be a bronze or gold color. If you don’t see this color, the filter is likely clogged with hydraulic fluid and requires prompt replacement.
Checking Bearing Oil
You might own an excavator or machine with a final drive equipped with a main bearing requiring a specialized lubricant. You’ll need to check the oil every 500 service hours and add more via the drainage holes on the drive’s motor when necessary. You can also drain the old oil at the same location when it’s time for a change.
Servicing the Undercarriage
Undercarriages can quickly become clogged with dirt and debris, which can loosen the main seal and create final drive leaks. Make undercarriage cleaning part of your maintenance practices to help keep the final drive in peak condition.
Checking Hydraulic Fluid
Hydraulics generate rotational mechanical energy that drives gears and wheels for tracked equipment. Hydraulic oil is susceptible to contamination, which can damage the final drive motor and impact its performance. Changing the hydraulic fluid approximately every 4,000 hours or at the manufacturer’s recommended interval is a vital preventive maintenance step.
Prime Source Can Meet All Your Final Drive Maintenance Needs
Turn to Prime Source Parts and Equipment to help keep your equipment’s final drive in peak operating condition. Our team of certified technicians can service models from all leading manufacturers.
If you own equipment with a final drive that isn’t working correctly, we have the resources and knowledge to diagnose the issue and perform timely repairs.
Do you have questions about final drives or need to schedule a service appointment? Call us at 704-610-5081 or contact us online today.