HOWO 420 Engine

The HOWO 420 engine is the legendary powerplant that has propelled Sinotruk vehicles to global dominance. With a robust 11.6L displacement, this 420 horsepower workhorse delivers 1820 Nm of peak torque between 1100-1400 rpm, ensuring effortless hauling in the toughest conditions. Built on the proven D12 platform, the HOWO 420 engine combines mechanical simplicity with advanced turbocharging and intercooling, offering fleet operators exceptional fuel economy and overhaul intervals exceeding 1,000,000 km. Whether powering a 6×4 tractor or a heavy-duty dump truck, this engine guarantees maximum uptime and lowest cost per kilometer.

Class‑Leading Power

Rated at 420 hp (309 kW) @ 2000 rpm, with massive torque of 1820 Nm available from just 1100 rpm. The HOWO 420 engine delivers instant response, pulling heavy loads effortlessly up steep grades without constant downshifting.

Exceptional Fuel Economy

Advanced combustion chamber design and optimized turbocharging reduce fuel consumption by up to 8% compared to predecessors. Fleet operators report average savings of $0.04 per mile with the HOWO 420 engine over long-haul operations.

Proven Durability

With induction‑hardened cylinder bores (126mm bore), forged steel crankshaft, and wet liners, the HOWO 420 engine achieves B10 life exceeding 1,000,000 km. Over 500,000 units in service worldwide attest to its legendary reliability.

Easy Maintenance

Modular design with service points on one side simplifies oil changes and valve adjustments. The HOWO 420 engine’s mechanical injection system (Euro II) is field‑serviceable anywhere, while common‑rail versions offer diagnostic flash codes for rapid troubleshooting.

Vg1246030001 Piston

OEM Vg1246030001 – High-strength piston for HOWO 420 engine, designed for optimal combustion and durability.

VG1246030002 Piston Pin

OEM VG1246030002 – Precision‑ground piston pin, case‑hardened for strength, ensures secure connection between piston and connecting rod.

VG1246060001 Tensioner Pulley

OEM VG1246060001 – Automatic belt tensioner pulley, maintains proper belt tension for accessory drives, reduces noise and vibration.

VG1246080050 Fuel Injection Pump

OEM VG1246080050 – High‑pressure fuel injection pump for HOWO 420 engine, ensures precise fuel metering and delivery for optimal power.

D12.42-20 (Euro II)

Displacement: 11.596L

Power: 420 hp (309 kW) @ 2000 rpm

Torque: 1820 Nm @ 1100-1400 rpm

Injection: Mechanical pump

Base model for 6×4 tractors and dump trucks, known for mechanical simplicity.

D12.42-30 (Euro III)

Displacement: 11.596L

Power: 420 hp @ 1900 rpm

Torque: 1850 Nm @ 1200-1500 rpm

Injection: Electronic unit pump

Enhanced version with improved fuel economy and lower emissions.

WP10.420E53 (Euro V)

Displacement: 9.726L

Power: 420 hp @ 1900 rpm

Torque: 1900 Nm @ 1200-1500 rpm

Injection: Common‑rail + SCR

Lighter 9.7L variant, ideal for long‑haul fleets needing Euro V compliance.

MC11.43-30 (Euro VI)

Displacement: 10.518L

Power: 430 hp @ 1900 rpm

Torque: 1900 Nm @ 1000-1400 rpm

Emission: Euro VI (EGR+SCR+DPF)

Latest generation with advanced telematics, used in HOWO TX series.

Heavy‑Duty Tractor Trucks

The HOWO engine is the standard power source for 6×4 tractor trucks (models ZZ4257V3241W, ZZ4257S3241W) handling 40-50 ton loads. Its 1820 Nm torque peak at 1100 rpm enables fuel‑efficient cruising at highway speeds with 12-speed HW19710 transmissions.

Dump Trucks & Construction

With reinforced block and heavy‑duty filtration, the HOWO 420 engine excels in 6×4 dump trucks (model ZZ3257N3847) and mining applications. It handles 25-ton payloads in extreme dust and heat, with cold‑start capability down to -30°C. Over 10,000 hours of service life reported in mines.

Proven Reliability

Over 500,000 HOWO engine units in service globally. B10 life of 1,000,000+ km and 20,000 hours before major overhaul.

Genuine Parts

All components are 100% OEM‑spec, sourced directly from Sinotruk’s approved suppliers. No aftermarket compromises on quality or fitment.

Expert Support

Factory‑trained engineers provide remote diagnostics via ECU flash codes (6= fuel system, 8=ignition). 4‑hour solution commitment through global network.

Fast Shipping

Global logistics network ensures HOWO engine parts reach you within 3‑5 business days. Express air freight available for critical breakdowns.

Often from valve cover gasket or rear main seal. Replace with genuine HOWO 420 engine gasket sets and torque to spec. Check oil cooler housing for cracks.

Check coolant level, fan clutch, and water pump. Clean radiator fins. HOWO engine thermostat should open at 82°C. Inspect viscous fan drive.

Clogged fuel filter, turbo boost leak, or injector fault. For Euro IV/V, check flash codes: 6 flashes = fuel delivery issue, 8 flashes = ignition system.

Check battery connections, fuel supply, and ECU power. Inspect crank position sensor and fuel pump relay.

“Our fleet of 22 HOWO tractors with the 420 engine has accumulated over 1.2 million km each. The torque at 1100 rpm is perfect for heavy loads, and fuel consumption averages 35L/100km.”

— Andrei, fleet owner, Romania

“I’ve been driving HOWO 420 engines for 8 years. They start instantly even at -35°C in Siberia. Simple mechanical injection means I can fix most issues myself on the road.”

— Viktor, long‑haul driver, Kazakhstan

“We operate 15 HOWO 420 dump trucks in a copper mine. After 25,000 hours, three engines have never been opened. Parts availability through this supplier is outstanding.”

— Thomas, maintenance manager, Zambia

“Upgraded to common‑rail HOWO 420 Euro V engines last year. Fuel savings of 8% compared to our older fleet, and the diagnostic flash codes make troubleshooting quick.”

— Miguel, transport director, Mexico

“The HOWO 420 engine in our 6×4 tanker handles 45 tons of fuel daily. Climbing mountain passes, it never loses power. Rebuild at 900,000 km cost half of a new engine.”

— Ali, logistics manager, UAE

“As a mechanic specializing in Sinotruk, I recommend the HOWO 420 engine for its simplicity. Parts are standardized and always available. The 430mm clutch mates perfectly with the torque curve.”

— Juan, workshop owner, Colombia

Precision Fuel‑Air Combustion

The HOWO 420 engine operates on a meticulously orchestrated four‑stroke cycle. High‑pressure injection (up to 1800 bar in common‑rail versions) atomizes fuel into fine droplets, ensuring thorough mixing with turbocharged air. The 17:1 compression ratio enables complete combustion, extracting maximum energy from every drop of fuel.

Mechanical Power Transmission

Linear piston motion is converted to rotational force via forged steel connecting rods and a induction‑hardened crankshaft. The HOWO 420 engine’s power is transmitted through a 430mm diaphragm spring clutch (HW19710 transmission) with hydraulic air assistance, delivering smooth engagement even under 50-ton loads.

Oil & Filter Changes

Use genuine HOWO 420 engine oil filters and high‑quality diesel engine oil. Change every 30,000 km to prevent sludge buildup. Always prime the oil filter before installation to avoid dry starts.

Cooling System Care

Check coolant concentration and change every 2 years. Inspect hoses and clamps to avoid overheating and head gasket failure. Use only OAT coolant specified for the HOWO 420 engine to prevent cavitation.