Breaking Tracks on the Case 455C and Field Techniques for Undercarriage Service

[MikePhua]

The Case 455C and Its Undercarriage Configuration
The Case 455C crawler loader was introduced in the late 1980s as part of Case’s evolution from the 455B series. Designed for rugged earthmoving, demolition, and site prep, the 455C featured a turbocharged diesel engine producing around 80 horsepower, hydrostatic drive, and a sealed and lubricated track system. With an operating weight of approximately 16,000 lbs, it offered a balance of power and maneuverability for mid-size contractors and municipal fleets.
The undercarriage was built around a sealed track chain with master pin assembly, tensioning idlers, and track rollers mounted to a rigid frame. While durable, the track system requires periodic service—especially when pins wear, bushings elongate, or tensioning fails. Breaking the track is a necessary step for replacing rollers, sprockets, or adjusting chain length.
Terminology annotation:

• Master Pin: A removable pin in the track chain that allows the track to be separated for service.
  
• Track Chain: A continuous loop of steel links and bushings that drive the machine over terrain.
  
• Track Tensioner: A hydraulic or spring-loaded mechanism that maintains proper chain tension.
  
• Track Press: A specialized tool used to remove and install track pins under high force.
  

Challenges in Breaking the Track
Breaking the track on a Case 455C can be physically demanding and requires precision. The master pin is often rusted, mushroomed, or seized from years of vibration and environmental exposure. Without proper tools and technique, attempts to drive out the pin can result in damage to the chain or injury to the technician.
Common obstacles:

• Master pin not clearly marked or misaligned
  
• Pin ends flared from wear or previous hammering
  
• Track tension not fully released, causing binding
  
• Lack of clearance between track and frame
  
• Cold weather increasing metal contraction and resistance
  

Recommendations:

• Identify master pin by locating the link with a centered dimple or weld mark
  
• Release track tension fully by backing off the idler or bleeding hydraulic pressure
  
• Use heat to expand pin bore and soften rust bonds
  
• Grind mushroomed ends flush before driving
  
• Support track on cribbing to prevent sag and rebound
  

In Minnesota, a contractor used a torch to heat the master pin for 10 minutes before striking with a 20-lb sledge and drift. The pin moved after three blows, saving hours of frustration and avoiding damage to the adjacent links.
Tools and Techniques for Efficient Removal
While some operators rely on brute force, using the right tools can dramatically improve safety and efficiency.
Recommended tools:

• Heavy-duty pin punch or drift (hardened steel)
  
• 20–30 lb sledgehammer
  
• Oxy-acetylene torch for localized heating
  
• Angle grinder for end preparation
  
• Hydraulic track press (if available)
  
• Safety glasses, gloves, and steel-toe boots
  

Step-by-step process:

• Park machine on level ground and block tracks
  
• Release tensioner fully and allow track to relax
  
• Locate master pin and clean surrounding area
  
• Grind pin ends flush if flared
  
• Heat pin area to 400–600°F to expand bore
  
• Strike with drift and sledge until pin moves
  
• Remove pin and separate track chain
  

Precautions:

• Never strike directly with hammer—use drift to avoid shattering pin
  
• Avoid over-heating which may damage seals or bushings
  
• Keep bystanders clear of swing zone
  
• Use cribbing to support track and prevent collapse
  

In British Columbia, a forestry crew built a portable track press using a bottle jack and steel frame. The device allowed them to break tracks in the field without relying on heat or hammering, reducing downtime during remote operations.
Reassembly and Tensioning Best Practices
After servicing the undercarriage, rejoining the track requires alignment and proper tensioning. Misaligned links can cause premature wear or derailment.
Reassembly tips:

• Align track ends using pry bars and ratchet straps
  
• Insert master pin with anti-seize compound
  
• Tap pin gently until fully seated
  
• Re-tension track to manufacturer spec (typically 1–2 inches sag at midpoint)
  
• Cycle machine forward and reverse to confirm alignment
  

Recommendations:

• Replace master pin if worn or bent
  
• Inspect bushings and links for cracks or elongation
  
• Grease idler and roller bearings during reassembly
  
• Record service date and track hours for future reference
  

In Texas, a contractor added tensioning checks to his weekly maintenance routine. This reduced track derailments and extended chain life by 25% across his fleet of Case loaders.
Conclusion
Breaking the track on a Case 455C is a rite of passage for many field mechanics. It demands patience, preparation, and respect for the forces involved. With the right tools, clear technique, and a safety-first mindset, the task becomes manageable—even in the mud, snow, or heat. In the world of crawler loaders, the track is the lifeline—and knowing how to break and rebuild it is the mark of a seasoned operator.