Yanma

The VIO55 sits in Yanmar‘s compact excavator lineup, positioning itself as a premium option in the 5–5.5 ton class. It is designed for operators who require the power and digging force of a larger machine but need to work in severely confined urban environments, utility repair sites, or densely packed landscapes. Its primary rivals include the Kubota KX057-5, Bobcat E55, and Caterpillar 305.5E. In this competitive field, the VIO55’s signature advantage is its true zero tail swing—engineering that ensures the machine‘s upper body never swings beyond the width of its tracks. The frame is built with a robust chassis, reinforced with spring steel structures that resist bending and increase durability. This allows operators to work confidently against walls, traffic, or existing structures without risking counterweight strikes, a feature that directly reduces liability and expands job site access. The machine also provides boom swing angles of 68° to the left and right, enabling offset digging without repositioning the tracks—a critical time-saver along walls or behind obstacles.

For used buyers, the VIO55 represents the sweet spot in the lineup: big enough to be productive on real excavation tasks, yet small and agile enough to fit where standard 7-ton machines cannot go. It is also available in a range of variants—the numeric suffix such as -5, -5A, or -6A indicates generational improvements, with later models (6B, 6A) offering upgraded electronics, engine tuning, and refinement over earlier ones like the original VIO55 or -5 series.

The VIO55 is built around a family of efficient and durable Yanmar diesel engines. The table below presents the core specifications based on the most common variants (VIO55-5A, VIO55-6A, and VIO55-5B). Note that specific values vary slightly between individual models and configurations, but the provided ranges cover the majority of machines found on the used market.

Note on variants: The VIO55 range includes multiple generations. Early units (2001–2007) weigh around 5,130 kg, while later -5A, -5B, and -6A models have slightly increased weights and upgraded engine management systems. All share the same zero tail swing design. Always confirm the exact variant and year before purchase, as parts compatibility varies.

The VIO55’s defining feature is its compact tail swing. When swinging the upper structure, the counterweight remains within the width of the tracks, preventing accidental strikes on nearby walls, barriers, or other equipment. This design allows operators to work within inches of obstructions, dramatically reducing the risk of costly collision damage and improving productivity on congested urban job sites.

The machine also features a dozer blade at the front for backfilling, grading, and stabilizing the machine during heavy digging. The blade can be raised and lowered hydraulically from inside the cab, adding versatility for landscaping and finishing work.

The VIO55‘s track width of 1,960–1,990 mm fits through standard residential gates and doorways, enhancing its utility on small-scale projects where larger machines cannot physically fit. Combined with a transport height under 2.6 meters, the VIO55 can be easily moved on a tilt-bed trailer without special permits or escorts.

The VIO55’s cab is designed for long-hour productivity. The operator platform is spacious and well-laid-out, with intuitive joystick controls and excellent all-round visibility—a critical safety feature for precision work and navigating tight job sites. Pressurization keeps dust out during dry operations, and large windows provide sightlines to the bucket edges and rear corners.

User feedback highlights several strong points:

• Smooth operation with low joystick effort: Operators praise the machine’s smooth hydraulics and low joystick pull, reporting that it reduces fatigue during long shifts. One user noted the joystick pull “seems to be less than most excavators” and that the control feel is exceptionally refined.

• Good climate control and ergonomics: Later models have effective HVAC systems for all-weather work. Some users note that while the cab is functional, it feels “a little claustrophobic” for operators accustomed to full-size excavators.

• Efficient auxiliary hydraulics: The auxiliary circuit delivers “plenty of thump” for hydraulic hammers, and the optional hydraulic quick coupler allows bucket changes “in less than 30 seconds,” significantly boosting attachment versatility.

A well-ventilated cab, adjustable seat, and easy-to-read LCD display are standard on later VIO55-6A models, providing real-time information on engine performance, hydraulic heat, and fuel consumption. However, some users have noted that the early VIO55 cabs are less refined.

Common complaints:

• Throttle lever placement: On earlier models, the throttle lever is located on the left-hand side of the seat in an awkward, inconvenient position rather than on the right console.

• Walk-through cab width: The cab is narrower than full-size excavators, which some larger operators find slightly restrictive for extended shifts.

For used buyers, checking the HVAC system (heating and cooling), seat condition, monitor operation, and any damage to glass or cab seals is essential. A well-maintained cab significantly enhances operator retention and daily productivity.

The VIO55’s hydraulic system is one of its standout technical features. Depending on the variant, the machine is equipped with a variable displacement piston pump that adjusts pressure and flow in real-time based on workload demands. More recent VIO55-6A models use a multi-pump arrangement delivering approximately 42.5 + 42.5 + 37 + 10.8 L/min through three separate circuits plus a pilot circuit. This design enables simultaneous operation of multiple functions—such as boom raising while swinging—without noticeable power loss or jerky movement, which is a major productivity advantage in tight cycle work.

Key hydraulic features include:

• Auto deceleration: When controls are idle for more than 4 seconds, the engine automatically drops to low idle speed, reducing fuel consumption and noise.

• Eco mode: Reduces maximum engine speed by approximately 15%, lowering fuel consumption while maintaining adequate power for lighter tasks.

• Isochronous speed control: When a heavy load is applied, the engine responds immediately by increasing fuel injection, preventing RPM drop and maintaining consistent swing and bucket speed even under high load.

The system relief pressure is set at approximately 24.5 MPa (3,553 psi) for the main hydraulic functions, delivering strong breakout force for breaking compacted soil or rocks. The industry-standard bucket digging force is rated around 33–43 kN, capable of handling most trenching and excavation tasks encountered in landscaping, utility, and light commercial construction.

For used buyers, evaluating the hydraulic system is critical, as this is one of the most common areas for wear and failure as the machine ages.