Rebuilding the Steering Cylinder on a John Deere 310D Backhoe

[MikePhua]

The JD 310D and Its Mechanical Legacy
The John Deere 310D backhoe loader, introduced in the early 1990s, was part of Deere’s highly successful 300-series lineup. Known for its reliability, hydraulic strength, and ease of service, the 310D featured a four-cylinder diesel engine, four-speed transmission, and robust hydraulic systems for both loader and backhoe functions. With thousands of units sold across North America, the 310D became a staple in municipal fleets, construction sites, and agricultural operations.
One of the more nuanced components of the 310D is its steering system, which relies on hydraulic cylinders to actuate the front wheels. Over time, these cylinders wear internally, leading to leaks, loss of steering precision, and eventual failure. Rebuilding the steering cylinder is a common maintenance task, but sourcing the correct seal kit and understanding the assembly nuances are critical to success.
Identifying the Correct Seal Kit
The first challenge in rebuilding the steering cylinder is identifying the correct seal kit. Deere’s parts catalog lists multiple cylinder variants depending on serial number, drive configuration (2WD vs. 4WD), and production year. For a 1995 model with serial number TO310DA813849, the correct seal kits are typically:

• AH167552 for the bore seals
  
• RE21875 for the rod seals
  

These kits correspond to the cylinder variant used in 2WD configurations. Ordering the wrong kit—such as RE18749—can result in mismatched seals and wasted time. Technicians are advised to disassemble the cylinder first and match internal components visually or by part number before ordering.
Terminology Annotation

• Bore Seal: Seals that prevent fluid leakage between the cylinder barrel and the piston
  
• Rod Seal: Seals that prevent fluid from escaping around the moving rod
  
• Gland: The end cap of the cylinder that houses the rod seals and guides the rod
  
• Snap Ring: A retaining ring that holds the gland in place within the cylinder barrel
  

Disassembly and the Role of the Orange Filler Ring
During disassembly, technicians may encounter an orange chamfered ring inside the gland. This ring, often mistaken for a sealing component, is actually a filler used to bridge the retaining groove during seal removal. Its teardrop-shaped cross-section allows seals to pass over the groove without damage.
Importantly, this filler ring should not be reinstalled during assembly. If left in place, it can interfere with the snap ring seating, potentially allowing the gland to eject under pressure—resulting in sudden loss of steering and hydraulic fluid. One operator discovered this the hard way, noting that the snap ring sat 1/16" shy of its groove until hydraulic pressure was applied. This workaround is risky and should be avoided.
Assembly Tips and Pressure Seating
After installing the new seals, the gland must be carefully reinserted into the cylinder barrel. If the snap ring does not seat fully, technicians may be tempted to use hydraulic pressure to push the gland outward. While this can work in some cases, it’s safer to:

• Lubricate the seals and gland with hydraulic fluid
  
• Use a soft mallet to gently tap the gland into position
  
• Ensure the snap ring groove is clean and free of debris
  
• Confirm the snap ring is fully seated before pressurizing the system
  

Failure to seat the snap ring properly can result in catastrophic failure under load.
Common Seal Failures and Material Observations
When disassembled, the original seals in the gland may appear deteriorated or missing. Fibrous packing material may be the only remnant of the original seal, and o-rings may be absent entirely. This leads to confusion during reassembly, especially if the technician waits days or weeks between teardown and rebuild.
To avoid guesswork:

• Photograph the cylinder components during disassembly
  
• Label each seal groove and note the seal type
  
• Compare old seals to new ones before installation
  

Some glands feature a chamfered groove that appears to require a seal, but may not. If unsure, consult the parts diagram or a hydraulic specialist.
Field Anecdotes and Practical Advice
One technician shared that after rebuilding his 310D’s steering cylinder, he noticed no leaks but remained cautious about the orange filler ring. After learning it was only for disassembly, he removed it and reseated the gland properly. Another operator noted that his local Deere dealer was unable to identify the correct kit, prompting him to use online resources and match parts manually.
These stories highlight the importance of hands-on inspection and independent verification. Relying solely on dealer recommendations can lead to incorrect parts and delays.
Preventative Measures and Long-Term Maintenance
To extend the life of the steering cylinder:

• Replace seals every 2,000 hours or when leaks appear
  
• Use OEM-grade hydraulic fluid and filters
  
• Inspect rod surfaces for scoring or pitting
  
• Keep the cylinder clean and free of debris
  
• Avoid oversteering under load, which stresses the seals
  

Installing a protective boot over the rod can reduce contamination and seal wear, especially in muddy or abrasive environments.
Conclusion
Rebuilding the steering cylinder on a John Deere 310D requires attention to detail, correct part identification, and an understanding of hydraulic assembly principles. By avoiding common pitfalls—such as reinstalling the orange filler ring—and verifying seal placement, operators can restore precise steering and prevent future failures. With proper technique and preventative care, the 310D remains a dependable workhorse in the field, ready to tackle the next trench, load, or lift with confidence.