Kubota KX040-4

Parts Compatible with the Kubota KX040-4 Mini Excavator

The KX040-4 is the 4 ton class entry in Kubota's current 4 Series mini excavator lineup, replacing the legacy 3 Series KX121-3 in this size class. The 4 Series introduced Tier 4 Final emissions compliance across the line, refreshed cab and operator station design, and added the optional hydraulic 6-in-1 blade that gives the machine grading and dozing functionality typically found on much larger machines. The KX040-4CA designation is the Canadian spec variant of the same machine, sharing the chassis, drivetrain, hydraulics, and engine with the base KX040-4 plus regulatory compliance items specific to Canada. Many KX040-4 service parts cross to the KX033-4 (the 3.4 ton sibling in the same 4 Series lineup) and to the KX057-4 (the 5 ton sibling) because Kubota engineered the 4 Series machines on a shared parts platform with engine and hydraulic system as the primary scale variables.

Cab glass on the KX040-4 cabin variants uses the RD451 series dimensions, which is unique to the 4 Series cab generation and does not interchange with the legacy RC411 series glass on the KX121-3 / KX161-3 cabs. Many other 4 Series cab service parts cross between KX040-4 and U35-4 because Kubota harmonized cab components across the conventional and minimum tail swing lines in the 4 Series. The Tier 4 Final fuel system uses the water separator HHV00-51920 in addition to the primary fuel filter, with the V0631-51880 fuel filter having a serial number specific fitment that the product page documents.

Common Replacement Parts for the Kubota KX040-4

Engine service uses Engine Oil Filter RD159-51940 (the 4 Series specific filter cross referenced from the V2607-CR-E4 engine family) and Air Filter RD158-42280 (the 4 Series specific air canister). Cab Air Filter 6A671-75090 covers the KX040-4 cab climate system. Fuel filter V0631-51880 fits the V2607-CR-E4 engine fuel system, and the product page calls out the serial number constraint where applicable.

Cold weather start service uses Frost Plug Heater 70000-00297 (a 4 Series specific accessory that block heaters into the engine for sub-freezing operation). Cab service parts include Rear View Mirror 36919-53340, Fuel Cap R5611-51120 with the lockable variant covering theft-prevention service, and Ignition Switch RC461-53960. Smaller assembly hardware (Oil Gauge Plug 1G513-36550, Guide Oil Gauge 17456-36420, Shim RD451-19180, O-Ring 04817-50300, Washer 04512-50080, Washer 04512-50120) covers routine top end work.