Operator Comparison Between the Caterpillar 390D and John Deere 870G Excavators

[MikePhua]

The Evolution of Large Excavators in Heavy Construction
Caterpillar and John Deere have long competed in the high-capacity excavator market, each offering machines tailored for mass excavation, quarry work, and infrastructure development. The Caterpillar 390D and John Deere 870G represent flagship models in their respective lineups, designed to move thousands of cubic meters of material per day. Both machines are engineered for durability, hydraulic precision, and operator comfort, but their design philosophies diverge in ways that become apparent from the operator’s seat.
Caterpillar, founded in 1925, has dominated the global earthmoving sector for decades. The 390D was introduced as part of the D-series, replacing the 385C and offering improved hydraulic efficiency, reinforced structures, and advanced electronic monitoring. John Deere, with roots in agricultural machinery since 1837, expanded its construction division aggressively in the 2000s. The 870G is part of the G-series, built to deliver high breakout force and fuel efficiency in demanding environments.
Engine Power and Hydraulic Response
The 390D is powered by a Cat C18 ACERT engine producing approximately 523 hp, while the 870G uses a John Deere PowerTech 13.5L engine rated at around 512 hp. While the horsepower figures are close, the hydraulic tuning differs:

• 390D: Prioritizes smooth multi-function control with load-sensing hydraulics
  
• 870G: Emphasizes raw digging force and fast cycle times with high-flow circuits
  

Operators often describe the 390D as “fluid and predictable,” especially during simultaneous boom and swing operations. The 870G, by contrast, feels “aggressive and responsive,” ideal for deep trenching or rock breaking.
In Alberta, a contractor noted that the 870G outpaced the 390D in trench production by 12% over a week, but the Cat offered better control when placing riprap near bridge abutments.
Cab Comfort and Operator Interface
Both machines feature spacious cabs with air suspension seats, climate control, and ergonomic joystick layouts. However, the user interface and visibility differ:

• 390D: Offers a larger touchscreen monitor with customizable layouts and diagnostics
  
• 870G: Uses a simpler display with tactile buttons and fewer menu layers
  

Visibility from the 390D is enhanced by a lower boom pivot and wide glass panels. The 870G compensates with a high-mounted seat and narrower pillars. Noise levels in the Cat are slightly lower due to better insulation and engine compartment baffling.
In Shanghai, an operator working 12-hour shifts preferred the 390D for its quieter cab and intuitive controls, especially during night operations.
Undercarriage and Stability
The 390D weighs approximately 90 metric tons, while the 870G comes in around 85 metric tons. Both use reinforced X-frame undercarriages with sealed track chains and heavy-duty rollers. The Cat’s longer track frame provides better stability during extended reach work, while the Deere’s shorter frame improves maneuverability in tight quarry benches.

• 390D: Better suited for slope work and long-reach applications
  
• 870G: More agile in confined spaces and easier to reposition
  

Some operators retrofit counterweights or boom dampers depending on the job. In Ohio, a crew added a custom counterweight to the 870G for lifting precast culverts, improving rear stability without compromising swing speed.
Fuel Efficiency and Maintenance Access
Fuel consumption varies by task, but averages:

• 390D: 18–22 gallons per hour
  
• 870G: 16–20 gallons per hour
  

The Deere’s engine tuning and hydraulic regeneration system offer slight fuel savings during repetitive cycles. Maintenance access is easier on the 870G, with grouped service points and wide-opening panels. The 390D requires more reach for filter changes but compensates with onboard diagnostics and fluid sampling ports.
In Baghdad, a contractor noted that the 870G’s centralized grease banks reduced daily service time by 30 minutes compared to the 390D.
Operator Preferences and Jobsite Suitability
Operator feedback often depends on task type:

• For precision work like pipe laying or slope shaping, the 390D is favored for its control finesse
  
• For bulk excavation or demolition, the 870G is preferred for its breakout force and fast cycles
  

Some crews alternate machines based on phase. In trenching operations, the Deere leads the cut while the Cat handles cleanup and placement. In mass excavation, both machines are paired with 40-ton trucks, but the 870G’s faster swing speed often fills beds quicker.
Conclusion
The Caterpillar 390D and John Deere 870G are both exceptional machines, each with strengths that appeal to different operator styles and jobsite demands. The 390D excels in control, comfort, and long-reach stability, while the 870G delivers speed, power, and service simplicity. From the operator’s view, the choice often comes down to task type, terrain, and personal preference. With proper maintenance and skilled hands, either machine can anchor a high-production excavation fleet for years to come.