Reclaiming the Heart of a CAT 980B Transmission

[MikePhua]

The CAT 980B and Its Role in Heavy Loading
The Caterpillar 980B wheel loader was introduced in the early 1970s as part of Caterpillar’s second-generation articulated loaders. Designed for quarrying, mining, and bulk material handling, the 980B featured a robust frame, high breakout force, and a torque converter transmission that allowed smooth gear transitions under load. With an operating weight exceeding 50,000 pounds and a bucket capacity of up to 6.5 cubic yards, the 980B became a staple in aggregate yards and large-scale earthmoving operations.
Caterpillar, founded in 1925, had already established dominance in dozers and graders. The 980B reinforced its reputation in the loader category, with thousands of units sold globally. Its transmission system—an integral part of its performance—was engineered to handle high torque loads and frequent directional changes, making it one of the most durable components in the machine.
Disassembling a Transmission for Salvage
When a 980B transmission is dismantled for parts, it presents a rare opportunity to recover high-value components that are increasingly difficult to source. In one case, a complete transmission was taken apart, with all internal parts reportedly in excellent condition. This includes:

• Planetary gear sets
  
• Clutch packs and pressure plates
  
• Torque converter assembly
  
• Valve body and solenoids
  
• Input and output shafts
  
• Transmission housing and inspection covers
  

Each of these components plays a critical role in the loader’s ability to shift under load, maintain traction, and deliver consistent power to the wheels. Salvaging them not only supports other machines in the field but also preserves the legacy of a model that’s no longer in production.
Why Transmission Parts Are in High Demand
As 980B units age, sourcing OEM transmission parts becomes increasingly difficult. Caterpillar has phased out direct support for many components, and aftermarket suppliers often focus on newer models. For operators still running 980Bs, the availability of clean, used parts can mean the difference between continued operation and forced retirement.
Common failure points include:

• Worn clutch discs due to heat and friction
  
• Cracked planetary gears from shock loading
  
• Leaking seals and gaskets
  
• Stuck or misfiring solenoids in the valve body
  

Rebuilding a transmission with salvaged parts can restore full functionality at a fraction of the cost of a remanufactured unit. However, it requires careful inspection, cleaning, and sometimes machining to ensure tolerances are within spec.
Inspection and Reuse Guidelines
Before reusing any transmission component, follow these steps:

• Clean all parts with solvent and compressed air
  
• Inspect gear teeth for pitting, spalling, or deformation
  
• Measure clutch pack thickness and spring tension
  
• Pressure test the torque converter for internal leaks
  
• Check shaft runout with a dial indicator
  
• Replace all seals and gaskets with new equivalents
  

If the transmission housing is intact and free of cracks, it can be reused after thorough cleaning and repainting. Valve bodies should be disassembled and flushed to remove any debris or varnish buildup.
Field Anecdotes and Restoration Success
A quarry operator in Alberta rebuilt his 980B transmission using salvaged parts from a dismantled unit. After replacing the clutch packs and reconditioning the valve body, the loader returned to service and operated for another 3,000 hours without issue. He noted that the planetary gears were in better shape than expected, and the torque converter only needed seal replacement.
In another case, a contractor in Nevada used salvaged solenoids and pressure plates to repair a transmission that had lost reverse gear. The repair cost less than $5,000, compared to a $25,000 quote for a remanufactured unit.
Preserving the Legacy of the 980B
The CAT 980B may no longer be in production, but its impact on the industry remains. Machines still in operation rely on parts salvaged from retired units, and transmission components are among the most valuable. By dismantling and cataloging these parts, operators and rebuilders keep the 980B alive—one gear at a time.
For those with access to a dismantled transmission, consider documenting part numbers, wear patterns, and compatibility with later models like the 980C. This information can support rebuilds across fleets and contribute to the broader knowledge base of legacy Caterpillar equipment.
Conclusion
A dismantled 980B transmission is more than a pile of metal—it’s a reservoir of mechanical potential. With careful inspection and reuse, its components can breathe new life into loaders still working the earth. In an industry where uptime is everything, salvaged parts offer a practical and respectful way to honor the machines that built the modern landscape.