Dresser 515B Steering Cylinder and Center Hitch Repair Strategy

[MikePhua]

The Dresser 515B Loader and Its Mechanical Foundation
The Dresser 515B wheel loader was introduced in the mid-1980s as part of Dresser Industries’ push to modernize its compact earthmoving lineup. Built for utility contractors, municipalities, and small aggregate operations, the 515B featured a 4WD drivetrain, a mid-size frame, and a robust hydraulic system. Powered by a reliable diesel engine—often the DT-466 or equivalent—the machine offered a balance of maneuverability and lifting capacity in tight job sites.
Dresser Industries, originally a petroleum equipment manufacturer, entered the construction equipment market through acquisitions and partnerships. By the time the 515B was released, Dresser had merged with Komatsu, and many of its machines shared components and service support with Komatsu’s global network. Though production ceased decades ago, the 515B remains in service across North America, supported by aftermarket parts and dedicated rebuilders.
Steering Cylinder Pins and Bushings Replacement
One of the most common wear points on the 515B is the steering cylinder assembly—specifically the pins and bushings that anchor the hydraulic cylinders to the loader frame. These components endure constant stress during articulation, especially in tight turns or uneven terrain.
Terminology Annotation:

• Steering Cylinder: A hydraulic actuator that pivots the front and rear frames of an articulated loader.
  
• Pin and Bushing: A mechanical joint where a steel pin rotates inside a bronze or composite sleeve, allowing controlled movement.
  
• Boss: The reinforced housing or bracket on the frame where the cylinder mounts.
  

Replacing worn pins and bushings is generally straightforward unless the pins are seized or the bosses are damaged. If the pins are free-moving, the job involves:

• Supporting the loader frame with cribbing or jacks
  
• Removing retaining bolts and hydraulic lines
  
• Extracting the pins with a slide hammer or press
  
• Installing new bushings using a driver and lubricant
  
• Reassembling with torque specs and fresh grease
  

Estimated cost:

• Parts: $150–$300 for OEM or aftermarket kits
  
• Labor: 4–6 hours for experienced technicians
  
• Tools: Slide hammer, bushing driver, torque wrench, hydraulic line caps
  

In Massachusetts, a contractor replaced both steering cylinder bushings on a 1987 515B using a homemade press and a propane torch to expand the bosses slightly. The job took one afternoon and restored steering precision immediately.
Center Hitch Wear and Frame Repair
If steering issues persist after cylinder service, the root cause may lie in the center hitch—the articulated joint connecting the front and rear frames. Over time, the bearings and bores in this joint wear out, causing misalignment, excessive play, and uneven tire wear.
Repairing the center hitch involves:

• Splitting the loader at the articulation joint
  
• Removing the hitch pins and bearings
  
• Inspecting bore condition with a dial gauge
  
• Welding and machining worn bores back to spec
  
• Installing new bearings and seals
  

Terminology Annotation:

• Center Hitch: The pivot point between the front and rear halves of an articulated loader.
  
• Bore: The cylindrical cavity where bearings sit; must be concentric and smooth.
  
• Machining: The process of cutting or grinding metal to precise dimensions.
  

This repair is technical and requires specialized tools such as boring bars, weld preheat equipment, and precision measuring instruments. It is not recommended for novice mechanics or field conditions.
Estimated cost:

• Parts: $500–$1,200 depending on bearing type
  
• Labor: 20–30 hours including machining
  
• Shop services: $1,500–$3,000 for bore welding and re-cutting
  

In Arizona, a fleet manager rebuilt the center hitch on three 515Bs using a mobile machine shop. The investment extended the service life of each loader by over 5,000 hours and eliminated chronic steering drift.
Parts Availability and Sourcing Strategy
Although Dresser-branded parts are no longer manufactured, many components are interchangeable with Komatsu equivalents or available through aftermarket suppliers. Key sources include:

• Komatsu dealerships with legacy support
  
• Heavy equipment salvage yards
  
• Online vendors specializing in vintage loaders
  
• Custom machine shops for bushings and pins
  

Recommendations:

• Always verify part numbers against casting codes
  
• Use hardened steel pins with grease grooves
  
• Choose bushings with graphite or moly coating for dry environments
  
• Keep spare seals and shims on hand for future service
  

Preventative Maintenance and Inspection Tips
To avoid steering and hitch failures:

• Grease all pivot points weekly
  
• Inspect for play or misalignment monthly
  
• Replace worn bushings before they damage bosses
  
• Monitor hydraulic pressure and cylinder drift
  
• Log steering effort and tire wear as early indicators
  

Installing a steering angle sensor or frame alignment gauge can help detect wear before it becomes structural. In high-duty cycles, consider rebuilding the hitch every 4,000–6,000 hours.
Conclusion
The Dresser 515B remains a capable and serviceable loader, but its steering system demands attention as it ages. Replacing cylinder pins and bushings is manageable for most operators, while center hitch repairs require professional machining. With proper diagnostics, parts sourcing, and preventative care, the 515B can continue working reliably in modern fleets. In the world of legacy loaders, precision and patience are the keys to keeping iron alive.