How to Replace Wear Pads on a John Deere 710D Extend-a-Hoe Without Damaging the Stick

[MikePhua]

John Deere 710D Backhoe Overview
The John Deere 710D is a heavy-duty tractor-loader-backhoe introduced in the 1990s, designed for deep trenching, utility work, and road maintenance. With a digging depth exceeding 17 feet and a powerful turbocharged diesel engine, the 710D was one of the largest backhoes in Deere’s lineup. Its extend-a-hoe feature allows the dipper stick to telescope outward, increasing reach and versatility. However, over time, the sliding mechanism develops play due to wear pad degradation, requiring precise and often labor-intensive replacement.
Terminology Notes

• Extend-a-Hoe: A telescoping dipper stick that increases reach without repositioning the machine.
  
• Wear Pads: Replaceable blocks or plates that guide and stabilize the sliding stick extension.
  
• Clevis Ear: The welded bracket where the bucket curl cylinder mounts; often obstructs removal of the stick extension.
  
• Air Arc Gouging: A process using compressed air and an electric arc to remove welds or metal.
  

Disassembly Strategy and Common Pitfalls
Replacing the wear pads on a 710D extend-a-hoe requires partial disassembly of the stick. The service manual recommends removing the clevis ear to slide the extension out. This step is critical but often underestimated.
Key steps include:

• Remove Bucket and Detach Cylinders: Begin by disconnecting the bucket and hydraulic cylinders to reduce weight and improve access.
  
• Air Arc or Torch the Clevis Ear: Use air arc gouging to remove the welds. A torch may be used, but access is limited and precision is critical.
  
• Withdraw the Extension Stick: Slide the stick out using a forklift or hoist. Ensure the cylinder is fully removed first—failure to do so can jam the barrel inside the stick.
  
• Access Hidden Fasteners: Six cap screws and dowel pins secure the upper support. These are located beneath the cylinder and must be accessed before reassembly.
  

Field Anecdote and Lessons Learned
In Minnesota, an electrician-turned-mechanic attempted the repair in his shop. After removing the clevis and pulling the cylinder pin, he tried to slide the extension out. It jammed. The cylinder rod had rotated and lodged itself in a hidden slot, blocking access to the internal fasteners. He had to cut a hole in the stick to manually rotate the barrel back into position. The barrel had also spun 180 degrees, causing hydraulic fittings to catch on internal edges.
The key lesson: remove the cylinder completely before attempting to slide the extension stick. Partial removal can lead to misalignment, internal jamming, and costly damage.
Reinstallation and Pad Compression
Once the old wear pads are removed, new blocks and plates must be installed. The challenge lies in compressing the new pads during reassembly.
Recommended techniques:

• Use Ratchet Straps or Hydraulic Presses: Apply controlled pressure to seat the pads against the plates.
  
• Grease Contact Surfaces Lightly: Reduces friction during insertion and prevents galling.
  
• Align Cylinder Ports Before Final Assembly: Prevents twisting and ensures smooth hydraulic function.
  

Recommendations for Technicians and Owners

• Follow the Manual Closely: Hidden fasteners and alignment steps are easy to miss.
  
• Use Air Arc Safely: Requires high airflow and skill—practice before attempting on critical welds.
  
• Inspect Cylinder Seals and Hoses: Replace while disassembled to avoid future leaks.
  
• Document Pin and Barrel Orientation: Prevents reassembly errors and speeds troubleshooting.
  
• Test Extension Movement Before Final Welding: Ensure smooth travel and pad contact before sealing the clevis.
  

Final Thoughts
Replacing wear pads on a John Deere 710D extend-a-hoe is a demanding but manageable task with the right preparation. The most common mistake—failing to remove the cylinder before sliding the stick—can lead to hours of rework and structural damage. With careful disassembly, proper tooling, and attention to alignment, the extend-a-hoe can be restored to factory performance, extending the life and precision of this powerful machine.