A Collector’s Fleet: Preserving the Legacy of Classic Crawlers and Track Loaders

This article explores a personal collection of vintage Caterpillar and Komatsu machines, including multiple generations of the CAT 955 and 977 series, the 951B, and a Komatsu D65E-6. These machines represent decades of evolution in tracked earthmoving equipment, each with its own mechanical personality, quirks, and historical significance. The collection reflects not only a passion for iron but also a commitment to preserving the working heritage of heavy equipment.

Terminology Notes

• Track Loader: A crawler machine with a front-mounted bucket used for digging, loading, and grading.
• Dozer: A crawler tractor equipped with a blade for pushing material.
• Undercarriage: The track system including rollers, idlers, sprockets, and track chains.
• Torque Converter: A fluid coupling that allows smooth transmission of power from the engine to the drivetrain.
• ROPS (Roll-Over Protective Structure): A safety frame designed to protect the operator in case of rollover.

The Fleet at a Glance

• CAT 955A, 955C, 955H, 955K, 955L
• CAT 951B
• CAT 977, 977A, 977H, 977K, 977L
• Komatsu D65E-6

Each model reflects a different era of Caterpillar’s design philosophy, from the early mechanical simplicity of the 955A to the hydraulic refinement of the 977L. The Komatsu D65E-6 adds a Japanese counterpoint, known for its fuel efficiency and robust undercarriage.

CAT 955 Series: Evolution of the Mid-Size Loader

The CAT 955 series began in the 1950s and continued into the 1980s, evolving through multiple variants:

• 955A: Early mechanical model with direct drive and basic hydraulics
• 955C/H: Introduction of torque converter and improved lift capacity
• 955K/L: Enhanced operator comfort, better visibility, and refined controls

These machines were widely used in construction, agriculture, and land clearing. The 955L, in particular, became a favorite for its balance of power and maneuverability.

A contractor in Georgia recalled using a 955L to clear pine stumps in red clay. “It wasn’t fast,” he said, “but it never quit. You could feel every root through the seat.”

CAT 951B: The Compact Workhorse

The 951B was a smaller track loader with a reputation for agility and reliability. It featured:

• 90–100 HP diesel engine
• Torque converter transmission
• Excellent visibility and tight turning radius

Ideal for urban demolition and utility trenching, the 951B was often seen in municipal fleets and small contractors’ yards. Its compact size made it easy to transport and service.

CAT 977 Series: Heavy-Duty Muscle

The 977 series was Caterpillar’s answer to high-capacity loading in rugged terrain. Key variants include:

• 977A: Early model with mechanical controls
• 977H/K: Introduction of hydraulic assist and improved lift geometry
• 977L: Final evolution with enhanced cab, better cooling, and stronger undercarriage

These machines were used in mining, quarrying, and large-scale earthmoving. The 977L could handle rock, clay, and demolition debris with ease.

One operator in Alberta described the 977K as “a brute with finesse.” He used it to load shot rock into haul trucks during winter, relying on its weight and traction to stay productive in icy conditions.

Komatsu D65E-6: The Japanese Challenger

The Komatsu D65E-6 is a mid-sized dozer known for its fuel efficiency and smooth hydraulics. Features include:

• 140–150 HP engine
• Powershift transmission
• Wide blade options for grading and pushing

Compared to its Caterpillar counterparts, the D65E-6 offers quieter operation and lower operating costs. It’s popular in forestry, road building, and land development.

A forestry crew in Oregon praised the D65E-6 for its ability to push wet timber slash without bogging down. “It’s light on its feet but strong in the push,” said the operator.

Restoration and Preservation Challenges

Maintaining a fleet of vintage machines requires dedication:

• Parts sourcing: Many components are obsolete, requiring salvage or fabrication
• Hydraulic leaks: Older seals and hoses degrade over time
• Electrical systems: Wiring insulation becomes brittle, leading to shorts
• Undercarriage wear: Track chains, rollers, and sprockets need regular inspection

Owners often keep donor machines or build custom bushings and brackets to keep their fleet running. One collector in Pennsylvania built a hydraulic hose press to fabricate his own lines for a 955K.

Operator Anecdotes and Field Wisdom

A retired operator in British Columbia shared how his 955H cleared snow from logging roads in the 1970s. “It didn’t have heat,” he said, “but it had heart. You learned to dress for the machine, not the weather.”

Another story comes from a demolition crew in Texas who used a 977L to tear down a brick warehouse. The loader’s weight and breakout force allowed it to shear walls cleanly, while the operator used the bucket curl to pull steel beams like toothpicks.

Conclusion: Iron with a Story

This collection of Caterpillar and Komatsu machines is more than a lineup—it’s a living museum of earthmoving history. Each model tells a story of innovation, labor, and resilience. Whether clearing land, loading trucks, or grading roads, these machines continue to serve with dignity and power. In the hands of a passionate owner, they are not just tools—they are legacy on tracks.