Gehl DL Transmission R&R: A Comprehensive Guide for Operators and Technicians

[MikePhua]

Gehl equipment is known for its ruggedness and reliability in the construction and agriculture sectors. However, like any machine subjected to intensive use, even Gehl equipment can face issues that require thorough repairs and replacements. One of the most challenging aspects of Gehl loaders and skid steers is dealing with transmission problems, specifically the removal and replacement (R&R) of the transmission in the DL series.
This article provides an in-depth look at the process of diagnosing and replacing the transmission in a Gehl DL series loader. We'll explore common symptoms of transmission issues, a step-by-step guide to the R&R procedure, and the importance of regular maintenance for optimal performance.
Understanding the Gehl DL Transmission System
The transmission in Gehl loaders, like the DL series, is a critical component that ensures smooth operation by controlling the speed and power distribution from the engine to the wheels or tracks. A hydrostatic transmission system is typically employed, which uses hydraulic fluid to power the drive motor, giving operators precise control over the machine's speed and movement.
Over time, the transmission system can develop issues such as fluid leaks, loss of power, or erratic behavior, often due to wear on the internal components. These issues can be difficult to diagnose, but once identified, the transmission may need to be completely replaced or rebuilt.
Common Symptoms of Transmission Problems
Before diving into the R&R procedure, it's important to understand the signs of transmission failure. Operators should be aware of these symptoms as early detection can prevent further damage and costly repairs:

1. Loss of Power
   A noticeable drop in the machine's power and speed may indicate that the transmission is struggling to deliver power from the engine to the drive wheels. This is often caused by low hydraulic fluid levels, a malfunctioning pump, or internal component wear.
   
2. Erratic Behavior
   If the loader or skid steer moves unpredictably—accelerating or decelerating without input from the operator—this could point to issues with the transmission's hydraulic system, such as a failing valve or pump.
   
3. Overheating
   Overheating can occur if there is insufficient fluid in the system or if the hydraulic fluid is contaminated. Excessive heat can cause seals to break down and metal components to wear more quickly, leading to eventual transmission failure.
   
4. Strange Noises
   Grinding or whining noises during operation are often a sign of mechanical failure inside the transmission. These sounds could indicate worn gears, bearings, or other internal components.
   
5. Fluid Leaks
   Hydraulic fluid leaks around the transmission area can point to worn seals or hoses. This reduces the fluid level and can lead to the loss of hydraulic pressure, which is essential for transmission operation.
   

The R&R Procedure for Gehl DL Transmission
Removing and replacing the transmission in a Gehl DL series loader is a complicated procedure that requires proper tools, knowledge, and patience. Below is a general step-by-step guide to help operators and technicians perform the R&R successfully.
Step 1: Preparation and Safety
Before beginning any work on the Gehl DL transmission, it’s essential to take necessary safety precautions:

• Disconnect the Battery: Ensure the loader is powered down and disconnect the battery to prevent accidental electrical shorts or system activations.
  
• Lift the Machine: Use a hydraulic lift or jack to elevate the loader or skid steer, ensuring it's stable and properly supported.
  
• Drain Hydraulic Fluid: Drain the hydraulic fluid from the transmission and hydraulic system. It's critical to use the proper waste disposal method for the used fluid.
  

Step 2: Remove Components for Access
The transmission is located within the drivetrain, which is often tightly packed with other critical components. To gain access, follow these steps:

1. Remove the Engine Cover: Most Gehl DL series models require the removal of the engine cover to access the transmission area. This step may involve undoing bolts or screws, depending on the model.
   
2. Disconnect Hydraulic Lines: Disconnect the hydraulic lines attached to the transmission. Take care to plug the open lines to prevent contamination.
   
3. Remove the Drive Shaft: The drive shaft connects the engine to the transmission. This must be disconnected before the transmission can be removed.
   
4. Remove the Axle or Rear Frame: Depending on the model, you may need to remove the rear axle or parts of the frame to free up the space around the transmission.
   

Step 3: Remove the Transmission
Now that access to the transmission is clear, it’s time to remove the faulty unit:

1. Unbolt the Transmission: Carefully unbolt the transmission from its mountings. The transmission is typically secured with heavy-duty bolts, so make sure to use the correct tools to avoid stripping the threads.
   
2. Lift the Transmission Out: With the help of a hoist or crane, lift the transmission out of the compartment. Be mindful of the weight of the transmission, as it can be quite heavy.
   

Step 4: Install the New Transmission
With the old transmission removed, it's time to install the replacement. Be sure to use a genuine Gehl replacement transmission for best results:

1. Position the New Transmission: Carefully lower the new transmission into position, ensuring that it aligns with the mounting points and the drive shaft.
   
2. Secure the Transmission: Bolt the new transmission in place, making sure it is tightly secured to prevent future movement.
   
3. Reconnect the Hydraulic Lines: Reconnect the hydraulic lines to the transmission, ensuring a proper seal to avoid leaks.
   

Step 5: Reassemble the Machine
Once the transmission is securely installed, the next step is to reassemble the rest of the machine:

1. Reattach the Drive Shaft: Connect the drive shaft to the new transmission, ensuring that the connection is tight and secure.
   
2. Reinstall the Rear Frame or Axle: Reattach any components that were removed to make space for the transmission, such as the rear axle or frame.
   
3. Refill Hydraulic Fluid: Refill the transmission and hydraulic system with the recommended hydraulic fluid. Make sure to use the right type and amount of fluid to prevent damage.
   
4. Reconnect the Battery: Finally, reconnect the battery to power the loader back on.
   

Step 6: Test the System
After reassembling the loader, it’s essential to test the system:

1. Check for Leaks: Start the engine and check for any hydraulic fluid leaks around the transmission and hoses.
   
2. Test the Transmission: Operate the machine through various speeds and functions to ensure the transmission is functioning smoothly without any issues like erratic behavior or unusual noises.
   

Preventive Maintenance for the Transmission System
Regular maintenance of the transmission system can prevent the need for costly repairs and replacements. Here are some key tips:

1. Check Hydraulic Fluid Regularly: Keep an eye on the fluid levels and the quality of the hydraulic fluid. Low or dirty fluid can cause the transmission to overheat or fail prematurely.
   
2. Inspect for Leaks: Regularly inspect the transmission for any signs of leaks. Catching small leaks early can prevent a larger issue down the line.
   
3. Change the Fluid as Recommended: Follow the manufacturer’s guidelines for fluid changes. Over time, fluid can break down, reducing its ability to lubricate and cool the transmission.
   
4. Monitor Machine Behavior: Be alert to any unusual behavior such as strange noises, loss of power, or erratic movements, which could indicate an issue with the transmission.
   

Conclusion: Keeping Your Gehl DL Loader Running Strong
Replacing the transmission in a Gehl DL series loader is a detailed and intensive process that requires skill and attention to detail. By following the outlined procedure, operators and technicians can replace a faulty transmission and restore the machine’s functionality.
Regular maintenance and early detection of transmission issues can significantly extend the life of the machine and avoid costly repairs. Whether you're a professional mechanic or an experienced operator, taking the time to properly care for your Gehl equipment will pay off in the long run, ensuring reliability and performance on the job site.