Introduction
Choosing between the Kubota U55-5 and KX057-5 isn't just about specs on paper. These two excavators dominate the 5-ton compact class, yet contractors struggle with the decision because both deliver Kubota's signature reliability while serving completely different operational needs.
The choice directly impacts your jobsite efficiency, maneuverability in tight spaces, digging capabilities, and project profitability.
Both machines share the same foundation. They belong to Kubota's latest "-5" generation launched in 2021, with identical 47.6 hp engines and operator environments.
The critical difference lies in tail swing design: the U55-5 features tight tail swing architecture optimized for urban work, while the KX057-5 uses conventional tail swing for maximum stability and reach in open environments. Understanding these distinctions helps contractors match equipment to actual site conditions rather than relying on specifications alone.
TL;DR
- U55-5 tight tail swing excels in confined urban sites and tight jobsites
- KX057-5 conventional tail swing delivers 10 inches more digging depth for open sites
- Identical hydraulic systems and 12,300 lb operating weights across both models
- Choose based on jobsite space constraints versus digging depth needs
Kubota U55 vs KX057: Quick Comparison
| Feature | Kubota U55-5 (Tight Tail Swing) | Kubota KX057-5 (Conventional) |
|---|---|---|
| Operating Weight | 12,247 - 13,007 lbs | 12,200 - 13,338 lbs |
| Engine Power | 47.6 HP @ 2,200 rpm | 47.6 HP @ 2,200 rpm |
| Max Digging Depth | 11'11" (3,630 mm) | 12'9" (3,875 mm) |
| Max Digging Reach | 19'7" (5,965 mm) | 20'1" (6,125 mm) |
| Bucket Breakout Force | 10,172 lbf | 10,172 lbf |
| Tail Swing Type | Tight tail swing | Conventional |
| Min. Tail Radius | 6'8" (2,020 mm) | 6'6" (1,990 mm) |
| Transport Length | 18'6" (5,635 mm) | 18'1" (5,520 mm) |
| Overall Width | 6'5" (1,960 mm) | 6'5" (1,960 mm) |
| Pump Capacity | 39.4 GPM total | 39.4 GPM total |
| Auxiliary Flow (AUX1/AUX2) | 19.8 / 9.8 GPM | 19.8 / 9.8 GPM |
| Travel Speed (Low/High) | 1.8 / 3.1 mph | 1.7 / 3.0 mph |
| Ground Pressure | 4.6 psi | 4.6 psi |
| Cab Display | 7" LCD touchscreen | 7" LCD touchscreen |
Transport and Dimensions
Both excavators maintain nearly identical transport profiles, fitting on standard equipment trailers without special permits. The U55-5 measures 18'6" in transport length versus the KX057-5's 18'1", a negligible 5-inch difference.
Both machines share the same 6'5" width and 8'4" height, simplifying fleet logistics for contractors running multiple units.
The similar dimensions mean both models navigate the same access points and trailer configurations. The primary consideration isn't transport size but rather the operational footprint once the machine is working—where tail swing design becomes the defining factor.
Hydraulic Performance
Beyond transport specs, the hydraulic systems perform identically across both models:
- Total pump capacity: 39.4 GPM (14.8 x 2 + 9.8 GPM)
- Operating pressure: 24.5 MPa (3,550 psi)
- AUX1 flow: 19.8 GPM for high-flow attachments like breakers and mulchers
- AUX2 flow: 9.8 GPM for auxiliary functions like thumbs and tilt buckets
Both machines feature adjustable auxiliary flow settings programmable through the 7" LCD panel, allowing operators to match hydraulic output to specific attachments without manual valve adjustments.
This standardization means attachment investments transfer seamlessly between models.
Cab Features and Operator Environment
Both models offer identical operator experiences:
- 7" LCD touchscreen display with customizable work mode settings
- Standard climate control with air conditioning and heating
- Keyless start system with passcode security
- Noise levels around 74 dB for full-day comfort
- Auto-idling system that reduces RPM after 4 seconds of inactivity
Visibility differences are minimal, though the U55-5's tighter counterweight profile provides marginally better sightlines to the right rear quadrant—an advantage when working in traffic or alongside structures.
What is the Kubota U55?
The U55-5 is Kubota's tight tail swing compact excavator designed specifically for confined-space operations where conventional machines create collision risks or require constant repositioning.
"Tight tail swing" means the counterweight extends minimally beyond the track width during rotation—not zero overhang like true zero-tail-swing models, but significantly less than conventional designs.
Core Specifications
- Engine: Kubota V2607-CR-E5, 47.6 gross HP (35.5 kW) at 2,200 rpm
- Operating weight: 12,247 - 13,007 lbs depending on configuration
- Maximum digging depth: 11'11" (3,630 mm)
- Maximum digging reach: 19'7" (5,965 mm)
- Bucket breakout force: 10,172 lbf
- Minimum tail turning radius: 6'8" (2,020 mm)
The 11'11" dig depth handles most utility trenching (typically 40-48 inches) and residential foundation work.
The machine's 12,300-lb operating weight provides stability without requiring heavy-duty transport, fitting comfortably on standard 14,000-lb equipment trailers.
Tight Tail Swing Advantage
The U55-5's counterweight geometry keeps the tail within approximately 6'8" of the machine's center of rotation. In practical terms, this allows operators to work with the machine positioned against walls, fences, or parked vehicles with minimal clearance concerns.
The design reduces the need for spotters in congested areas and improves safety in single-lane traffic closures.
While some overhang exists, the reduced swing radius dramatically expands where the machine can safely operate compared to conventional excavators that may require 8-10 feet of clearance behind the tracks.
Use Cases for the U55
Primary Applications:
- Urban utility installation alongside existing structures
- Residential landscaping in backyards with limited access
- Streetside trenching in single-lane closures
- Demolition work in congested commercial areas
- Any project where tail clearance creates safety or logistical challenges
Rental Market Context:
Compact excavators in the 3-5 ton class typically rent for $250-$400 daily, $900-$1,250 weekly, or $2,000-$2,500 monthly. Tight tail swing models command premium rates due to their specialized capabilities. Industry associations suggest hourly rates around $158 for excavators in this weight class.
Specific Scenario:
These capabilities translate directly to cost savings. Consider trenching for electrical conduit alongside a commercial building with only 8 feet between the structure and a parking lot. A conventional excavator would require constant repositioning or risk striking the building during rotation. The U55-5 operates safely in this envelope, completing the trench in a single pass without interruption. This efficiency translates directly to labor savings and reduced project timelines.
What is the Kubota KX057?
The KX057-5 represents Kubota's conventional tail swing approach in the 5-ton class, prioritizing maximum digging performance and stability over tight-quarter maneuverability.
The conventional design extends the counterweight beyond the track width, providing better balance during heavy lifting and full-reach operations.
Core Specifications
- Engine: Kubota V2607-CR-E5, 47.6 gross HP (35.5 kW) at 2,200 rpm
- Operating weight: 12,200 - 13,338 lbs depending on configuration
- Maximum digging depth: 12'9" (3,875 mm)
- Maximum digging reach: 20'1" (6,125 mm)
- Bucket breakout force: 10,172 lbf
- Minimum tail turning radius: 6'6" (1,990 mm)
The KX057 offers 10 inches more digging depth (12'9" vs 11'11") and 6 inches more reach (20'1" vs 19'7") than the U55. These differences matter for deep utility work, foundation excavation, and applications requiring maximum working area coverage from a single position.
Conventional Tail Swing Benefits
Extended counterweight geometry improves stability during lifting operations and when working at maximum reach.
Additional mass behind the pivot point counterbalances heavier bucket loads, reducing tipping risk and letting operators work more aggressively at the limits of the machine's capacity.
This design also distributes weight more effectively across the undercarriage, extending track life in heavy-duty applications. The trade-off? You'll need approximately 8-10 feet of clear space behind the machine during rotation.
Use Cases for the KX057
Primary Applications:
- Open-site construction and land development
- Deep utility installation (water mains, sewer lines exceeding 10 feet)
- Foundation excavation requiring maximum depth
- Agricultural projects including pond excavation and drainage work
- Road construction and site preparation where reach matters more than maneuverability
Digging Depth Impact
The 10-inch depth advantage is critical for utility contractors working on water and sewer mains that often require depths approaching 12 feet. The U55-5's 11'11" maximum leaves minimal safety margin at these depths. The KX057-5's 12'9" capacity provides comfortable working clearance without repositioning or benching down.
Specific Scenario:
Site preparation for a new commercial building requires excavating footings to 10 feet depth across a 40x60-foot footprint. The KX057-5 reaches the required depth from multiple positions, minimizing repositioning and maximizing cycle efficiency.
Its extended reach lets the operator maintain proper slope angles without constantly moving the machine, completing the excavation in fewer setups than a shorter-reach machine would require.
U55 vs KX057: Which Should You Choose?
The decision between these models hinges on jobsite geometry and application priorities rather than one machine being objectively superior.
Key Decision Factors
Choose the U55-5 when:
- Working in urban environments with buildings, fences, or overhead utilities
- Jobsite access limits clearance behind the machine during operation
- Primary applications include residential landscaping, utility work, or streetside trenching
- Maneuverability and safety in confined spaces outweigh maximum digging depth
- Projects involve frequent repositioning in tight quarters
Choose the KX057-5 when:
- Operating on open construction sites without space constraints
- Applications require maximum digging depth beyond 12 feet
- Extended reach reduces repositioning frequency and improves efficiency
- Stability during heavy lifting operations is a priority
- Primary work includes site development, road construction, or agricultural projects
Total Cost of Ownership Considerations
Both models share identical engines, hydraulic systems, and maintenance access designs, resulting in similar operating costs:
- Fuel consumption: Both feature auto-idling systems and load-sensing hydraulics that optimize fuel use
- Maintenance access: One-sided engine service design reduces maintenance time
- DPF management: Automatic regeneration prevents work stoppages
- Parts availability: Shared components across both models simplify inventory for multi-machine fleets
Resale Value:
Used U55-5 models from 2021 command $37,799-$68,950 depending on hours, demonstrating strong value retention. Both models benefit from Kubota's reputation for reliability, supporting long-term investment value.
Sourcing Through Mideast Equipment Supply
Contractors evaluating either model can use Mideast Equipment Supply's extensive network to locate specific units matching their requirements. With 12+ locations across the US and international shipping capabilities, the company provides access to used Kubota excavators.
Financing options through multiple competing lenders help contractors secure competitive terms, with business financing available starting at $1,388 per month for equipment in this class. Mideast Equipment Supply's equipment location service proves particularly valuable when specific configurations or low-hour units aren't immediately available. Their global dealer network sources machines meeting exact specifications, ensuring contractors find the right model for their attachment and operational needs.
Attachment Ecosystem Compatibility
Both models share identical attachment mounting systems and auxiliary hydraulic specifications:
- Compatible with standard two-hole quick couplers
- Hydraulic quick coupler options available for cab-operated changes
- Identical AUX1 and AUX2 flow rates (19.8 / 9.8 GPM)
- Operators can adjust flow settings through the LCD panel to match attachment requirements
This compatibility means contractors running mixed fleets of U55-5 and KX057-5 machines can share attachments—breakers, thumbs, augers, and specialty buckets—without adapters or modifications. The investment in attachments extends across both platforms, reducing total fleet costs.
Conclusion
Neither the Kubota U55-5 nor the KX057-5 is the better choice for every application—each excels in its intended environment.
The U55-5 delivers unmatched value in confined urban settings where tight tail swing prevents constant repositioning and reduces collision risks. The KX057-5 maximizes digging performance and stability for open-site applications where depth and reach drive productivity.
Choose the U55-5 when:
- Jobsite geometry constrains working space
- Tight tail swing is essential for urban work
- Frequent repositioning would slow productivity
Choose the KX057-5 when:
- Digging depth and reach are priorities
- Working in open sites with ample space
- Maximum stability matters for heavy lifting
Both machines deliver Kubota's characteristic reliability, operator comfort, and hydraulic performance. Strong resale values make either model a sound investment in the used equipment market, where dealers like Mideast Equipment Supply regularly source both configurations for contractors nationwide.
Evaluate your typical project profiles—urban versus open-site work—to determine which design philosophy matches your actual needs.
Frequently Asked Questions
What is the difference between the Kubota U55 and the KX057?
The primary differences are tail swing design (U55-5 tight vs KX057-5 conventional), digging depth (11'11" vs 12'9"), and reach (19'7" vs 20'1"). Both share the same 47.6 hp engine and hydraulic systems, but the U55-5 prioritizes maneuverability while the KX057-5 maximizes digging envelope.
How much weight can a Kubota U55 lift?
The U55-5 delivers 10,172 lbf bucket breakout force, though actual lifting capacity varies based on boom position and load radius. Always reference the machine's load chart for specific capacities at different working positions.
How much horsepower does a Kubota KX057 have?
The KX057-5 produces 47.6 gross horsepower from its Kubota V2607-CR-E5 engine at 2,200 rpm. This matches the U55-5's power output, as both models share the identical engine platform.
Which is better for tight spaces, U55 or KX057?
The U55-5's tight tail swing design makes it much better for confined spaces, with the counterweight staying closer to track width during rotation. This reduces the clearance zone required behind the machine, improving safety and efficiency.
What is the warranty coverage for Kubota excavators?
Kubota provides a standard 24-month or 2,000-hour limited warranty (whichever occurs first), with rubber tracks covered for 12 months or 1,000 hours. Extended warranty options are available through authorized dealers for contractors seeking additional coverage.
Can both models use the same attachments?
Yes, both models use compatible quick coupler systems and share identical auxiliary hydraulic flow specifications (19.8 / 9.8 GPM), making attachments fully interchangeable. This compatibility simplifies fleet management for contractors operating multiple units.
