Model Spotlight

Case CX42D Mini Excavator: D-Series 4.2-Ton Compact Excavator

The Case CX42D is a 4.2-ton D-Series mini excavator - a mid-compact machine built for utility, landscape, and light commercial digging in tight quarters where a larger tracked machine won’t fit. Tier 4 Final emissions, hydrostatic dual-path drive, and a rubber-track undercarriage define the D-Series mid-mini.

BT

Broken Tractor Editorial Team• Updated May 2026• 8 min read

Where the CX42D fits in the Case excavator line

The CX42D is a 4.2-ton class D-Series mini excavator. It slots into the Case compact excavator range as a solid mid-compact for utility, landscape, irrigation, plumbing, and light commercial digging - large enough to handle real production work, small enough to move between job sites on a standard equipment trailer and operate in residential settings without tearing up the property.

Engine, hydraulics, and drivetrain

The CX42D runs a small Tier 4 Final compact diesel into a hydrostatic dual-path drivetrain with a rubber-track undercarriage. Boom, dipper, bucket, swing, and propel functions all run from a main hydraulic pump with electrohydraulic or mechanical control, depending on configuration.

Tier 4 Final emissions compliance brings DPF particulate control and a DEF/SCR catalyst for NOx control. The compact diesel uses common-rail high-pressure injection - clean fuel and tight water separation are non-negotiable. The hydrostatic drive provides smooth modulation through the joysticks and pedals, and the rubber-track undercarriage gives flotation on finished turf and pavement-safe operation that steel-tracked machines can’t match.

Common service items on the CX42D

• Engine internals: Compact Tier 4 Final diesel - pistons, rings, sleeves, head gaskets, common-rail injection components.
• Tier 4 Final aftertreatment: DPF service intervals and regeneration behavior, DEF tank and dosing module, SCR catalyst, EGR cooler service.
• Fuel system: Common-rail injectors, lift pump, primary and secondary filters with tight water-separator standards.
• Cooling system: Radiator, water pump, thermostat, fan, charge-air cooler on turbo builds, hoses, belts.
• Hydraulic system: Boom, dipper, bucket, and swing cylinder seal kits, main pump rebuild components, electrohydraulic control valves, hoses.
• Boom and dipper: Pin and bushing service at every joint, bucket pins, thumb attachment hardware, quick coupler service.
• Undercarriage: Rubber track inspection and replacement, rollers, idlers, drive sprockets, recoil springs.
• Swing system: Swing motor and reduction gear service, swing bearing inspection, swing brake.
• Electrical / ECU: Engine ECU, instrument cluster, sensors, harness, telematics module on equipped units.
• Cab glass and wiper: KHN16820 24-inch wiper blade, KHN3046 front lower glass, and KHN2632 front upper glass cross-fit across Case and Link-Belt excavators.
• Operator station: Seat, joystick controls, pedal linkage, instrument panel, cab HVAC.

Parts and cross-fit components for the Case CX42D

What to verify before ordering

• Serial number. Confirm the machine serial on the CX42D before ordering year-specific parts - revisions ran through the D-Series production.
• Engine serial. Engine internal parts must match the engine serial number, not just the machine serial.
• Hydraulic cylinder bore. Cylinder seal kit fit depends on bore dimension - measure before ordering.
• Tier 4 emissions revision. DPF and DEF/SCR components saw revisions during production - confirm by serial.
• Engine ECU calibration. Common-rail injectors and ECU sensors are calibrated to specific build years.
• Bucket and quick coupler. Quick-coupler interface varies - confirm before ordering attachment-side hardware.

Why the CX42D still earns a paycheck

The Case CX42D is sized for compact-excavator duty cycles where a 4.2-ton machine is the right tool - residential landscape, utility, irrigation, plumbing, and any tight-quarters digging where larger excavators won’t fit. Modern Tier 4 Final emissions compliance, a compact footprint, and rubber-track flotation suit residential and contractor work where a wheeled or larger tracked machine would mark up turf or fail to fit between buildings.

Maintenance priorities on a CX42D: clean fuel and tight water separation for common-rail injection, DPF regen behavior tracking, hydraulic oil at temperature with clean filtration, rubber-track tension and wear monitoring, and pin and bushing service at every working joint. Broken Tractor maintains parts coverage across the Case mini excavator family - D-Series and adjacent generations.