Case 421G Wheel Loader: 2017+ G-Series Mid-Size Wheel Loader
The Case 421G is the entry point to Case's 2017+ G-series mid-size wheel loader range - Tier 4 Final diesel, power-shift transmission, G-series cab, and the chassis size that sits above the F-series compact line and below the 521G/621G production-class machines.
Where the 421G fits in the Case wheel loader line
The 421G is the smallest of Case's 2017+ G-series mid-size wheel loaders - above the F-series 321F compact line and below the 521G in the G-series production sequence. G-series brought updated cab ergonomics, refined electronic engine controls, and the visibility and operator interface that defined Case's mid-2010s wheel loader generation.
Case 421G Wheel Loader - Quick Specs
- Class
- Mid-Size Wheel Loader
- Generation
- G-Series, 2017+
- Frame
- Articulated
- Drivetrain
- Power Shift
- Engine
- Tier 4 Final Diesel
- Front Tool
- Hydraulic Loader
- Serial Plate Location
- Left Frame, Near Articulation Joint, Below Cab
- Smaller Sibling
- Case 321F (Compact)
- Larger Sibling
- Case 521G
What G-series brought to the mid-size class
- Engine. Tier 4 Final diesel with cooled EGR, DPF, and SCR aftertreatment for full current-tier emissions compliance.
- Cab. G-series operator station with electronic instrumentation, climate control, refined controls, and telematics integration.
- Hydraulics. Load-sensing piston pump driving electrohydraulic control valves and direct-acting loader cylinders.
- Drivetrain. Power-shift transmission, heavy articulated drive axles, planetary final drives, and wet-disc service brakes.
- Visibility and lighting. Improved sightlines and standard work lighting configurations across the G-series range.
Engine, hydraulics, and drivetrain
The 421G runs a Tier 4 Final diesel through a power-shift transmission and heavy articulated drive axles. Loader hydraulics use a load-sensing piston pump with electrohydraulic control valves and direct-acting cylinders. Wet-disc service brakes, planetary final drives, and the G-series cab handle electronic instrumentation, climate control, and telematics integration.
The articulated frame puts steering load on a pair of large steering cylinders pivoting the front and rear chassis halves around a heavy articulation joint. Pivot pins, bushings, and steering cylinder seal kits are recurring service items. Loader pin wear at the bucket, tilt link, and lift arm pivots is normal as hours accumulate.
Common service items on the 421G
- Engine internals: Tier 4 Final diesel pistons, rings, sleeves, bearings, gaskets, head service.
- Tier 4 aftertreatment: DPF, DEF tank and dosing module, SCR catalyst, EGR cooler service.
- Fuel system: Common-rail high-pressure injection, electronic injectors, lift pump, water-separator filtration.
- Cooling system: Radiator, water pump, thermostat, fan, charge-air cooler, hoses, belts.
- Loader hydraulics: Cylinder seal kits, load-sensing pump rebuilds, electrohydraulic control valves, hoses.
- Articulation steering: Steering cylinder seal kits, articulation pivot pins and bushings.
- Loader components: Bucket teeth, cutting edges, bushings, pivot pins, quick coupler.
- Drivetrain: Power-shift clutch packs, transmission components, axle seals, planetary final drives. Transmission shift lever assemblies move regularly.
- Brakes: Wet-disc service brakes. Service items include the S300718 brake shoe and recurring brake-cylinder rebuilds.
- Electrical / ECU: Engine ECU, instrument cluster, sensors, wiring harness, telematics module. The 87528688 AC blower speed resistor fits across 521E through 1121F.
- Cab / climate: G-series cab HVAC, the 47880728 cab fresh-air filter, controls, and gauges.
Parts we carry for the Case 421G
| Category | Common Parts | Browse |
|---|---|---|
| Engine | Tier 4 Final diesel internals | Browse Engine Parts |
| Aftertreatment | DPF, DEF, SCR, EGR components | Browse Aftertreatment |
| Fuel System | Common-rail injectors, lift pump, filters | Browse Fuel System |
| Cooling | Radiator, water pump, charge-air cooler, hoses | Browse Cooling |
| Loader Hydraulics | Load-sensing pump, cylinders, seal kits, valves, hoses | Browse Hydraulics |
| Articulation Steering | Steering cylinders, pivot pins, bushings | Browse Articulation Parts |
| Loader | Bucket teeth, cutting edges, pins, bushings | Browse Loader Components |
| Drivetrain | Power-shift clutch packs, transmission, shift lever | Shift Lever Assembly |
| Brakes | Wet-disc brake service, shoes, cylinders | S300718 Brake Shoe |
| Electrical | ECU, sensors, harness, blower resistor | 87528688 Blower Resistor |
| Cab | Cabin air filtration, blower resistor, controls | 47880728 Cab Filter |
Need a part for your Case 421G Wheel Loader?
Aftertreatment components, common-rail fuel system parts, and loader hydraulic seals are the highest-value items on a 421G. Call our parts team with your serial number.
Request a PartWhat to verify before ordering
- Serial number. Confirm the serial on the left frame near the articulation joint before ordering year-specific parts.
- Engine ECU calibration. Common-rail injectors and ECU sensors are calibrated to specific build years.
- Tier 4 emissions revision. DPF, DEF, and SCR components saw revisions during G-series production.
- Power-shift revision. Transmission clutch-pack revisions were issued during production.
- Cab vs. ROPS configuration. Operator station equipment varied.
Why the 421G still earns a paycheck
The 421G is Case's 2017+ entry into the G-series mid-size wheel loader range - the right size for contractors who need more capacity than an F-series compact but don't need the 521G/621G production class. Tier 4 Final emissions, power-shift drivetrain, modern cab visibility, and electronic engine controls round out the package.
Maintenance priorities on a 421G: clean fuel and tight water separation for common-rail injection, DPF/DEF/SCR service per Case schedule, hydraulic system condition, and brake service when actuation softens. Broken Tractor maintains parts coverage across the Case wheel loader family.
