Sinotruk HOWO, a flagship brand of China National Heavy Duty Truck Group (Sinotruk), stands as a symbol of resilience and power in the global commercial vehicle market. For over two decades, its heavy-duty trucks have dominated highways, construction sites, and mining operations—all thanks to the robust, fuel-efficient engines at their core. These engines are engineered to withstand extreme loads, harsh environments, and millions of kilometers of service.
Sinotruk HOWO’s engine lineup is designed for heavy-duty applications, where reliability and power are non-negotiable. The brand’s most popular series include the WD615, WD618, and MC Series (MC11/MC13), each tailored to specific hauling needs.
First introduced in the 1990s, the WD615 is a 6-cylinder, in-line diesel engine with a displacement of 9.726 liters. It delivers 260–375 hp (194–280 kW) and torque ranging from 950–1400 N·m.
Key Features: Cast-iron cylinder block for durability, turbocharged intercooling for improved air intake, and mechanical fuel injection (later upgraded to electronic control).
Applications: Medium-to-heavy trucks (10–25 tons), construction equipment (excavators, loaders), and mining support vehicles.
Why It Matters: The WD615 is a legend in China’s trucking industry, known for its simplicity and ability to operate in remote areas with limited maintenance.
The WD618 is a larger 6-cylinder engine with a 12.06 liters displacement, producing 380–480 hp (283–358 kW) and torque up to 1800 N·m.
Key Features: Reinforced crankshaft, high-pressure common-rail injection (for better fuel efficiency), and a dual-loop cooling system (to handle high temperatures).
Applications: Heavy-duty trucks (25–40 tons), long-haul logistics, and large mining trucks (e.g., hauling coal or ore).
Why It Matters: The WD618 is built for continuous high-load operation—perfect for China’s vast western regions, where trucks climb steep mountain passes with full loads.
Developed in collaboration with German engineering firms, the MC Series represents Sinotruk’s move into high-efficiency, low-emission engines.
MC11: 11 liters, 430–550 hp (321–410 kW), torque up to 2500 N·m.
MC13: 13 liters, 500–680 hp (373–507 kW), torque up to 3200 N·m.
Key Features: Lightweight aluminum cylinder head, variable geometry turbocharger (VGT), and selective catalytic reduction (SCR) for Euro V/VI emissions compliance.
Applications: Premium long-haul trucks (e.g., HOWO T7H), high-end logistics, and export markets (Europe, Southeast Asia).
Why It Matters: The MC Series combines German precision with Chinese manufacturing scale, offering fuel savings of 5–8% compared to older models—critical for fleet operators looking to reduce costs.
A Sinotruk HOWO engine’s durability depends on the quality of its internal components. Let’s break down the five most critical assemblies and explain how they contribute to performance:
The piston assembly is the “heart” of the engine, responsible for translating combustion energy into mechanical motion. It includes:
Piston: Forged from high-strength aluminum alloy (with a ceramic or graphite coating to resist wear).
Piston Rings: Three rings (compression, oil control) that seal the combustion chamber and prevent oil from entering the cylinders.
Piston Pin: Connects the piston to the connecting rod, made from hardened steel for strength.
Common Issues: Over time, piston rings can wear or become stuck (due to carbon buildup), leading to blow-by (combustion gases leaking into the crankcase) and increased oil consumption. For example, a WD615 engine with worn rings might burn 1–2 liters of oil per 1000 km—costly for fleet operators.
EPID Parts Support: We supply complete piston kits for all Sinotruk HOWO models, including forged aluminum pistons, chrome-plated rings, and precision piston pins. Our parts meet or exceed OEM specifications, ensuring a perfect fit and restoring engine compression.
The cylinder head and liner form the “combustion chamber envelope,” handling extreme heat and pressure.
Cylinder Head: Made from cast iron or aluminum (for MC Series), it houses the valves, fuel injectors, and coolant passages.
Cylinder Liner: A replaceable sleeve that lines the cylinder bore. Sinotruk HOWO engines use wet liners (in direct contact with coolant) for better heat dissipation—critical for heavy-duty operation.
Cylinder Head Gasket: A multi-layer steel (MLS) gasket that seals the gap between the head and block, preventing leaks of combustion gases, oil, or coolant.
Common Issues: A blown head gasket (caused by overheating or improper torque) can lead to coolant mixing with oil (visible as “mayonnaise” under the oil cap) or white smoke from the exhaust. Cylinder liners can also wear over time, increasing oil consumption.
EPID Parts Support: We offer genuine Sinotruk cylinder heads (for MC Series) and OEM-equivalent liners (for WD615/WD618) made from high-grade cast iron. Our MLS head gaskets are designed to withstand high pressure and temperature, reducing the risk of leaks.
Gaskets and seals are the “unsung heroes” of the engine, preventing leaks of oil, coolant, and fuel. Key components include:
Oil Pan Gasket: Seals the oil pan to the cylinder block, preventing oil leaks.
Valve Cover Gasket: Seals the valve cover to the cylinder head, keeping oil from leaking onto the engine.
Front/Rear Main Seals: Seal the crankshaft at the front (timing cover) and rear (flywheel housing), preventing oil from escaping the crankcase.
Common Issues: A leaking valve cover gasket can cause oil to drip onto the exhaust manifold (creating smoke and a burning smell), while a rear main seal leak can lead to significant oil loss.
EPID Parts Support: Our gasket sets for Sinotruk HOWO engines include all critical seals (oil pan, valve cover, main seals) in one package. Made from high-temperature resistant materials, they’re designed to last for 100,000+ km—reducing the need for frequent replacements.
The valve train regulates the intake of air and exhaust of gases, ensuring efficient combustion. It includes:
Valves: Intake (larger, for air) and exhaust (smaller, for hot gases) valves made from heat-resistant steel.
Valve Springs: Keep the valves closed when not in use. Sinotruk HOWO engines use double springs (for MC Series) to prevent valve float at high RPM.
Valve Guides & Seats: Guides support the valve stem, while seats provide a sealing surface for the valve face.
Common Issues: Valve guides can wear over time, causing oil to seep into the combustion chamber (leading to blue smoke). Exhaust valves can also burn (due to high temperatures), reducing engine power.
EPID Parts Support: We supply complete valve train kits for Sinotruk HOWO engines. Our parts are precision-machined to match OEM dimensions, ensuring smooth operation and proper sealing.
The connecting rod (con-rod) transfers motion from the piston to the crankshaft, converting linear motion into rotational power. It includes:
Connecting Rod: Forged from high-strength steel (for WD618/MC Series) to withstand compressive and tensile stresses.
Connecting Rod Bearings: Thin metal shells that reduce friction between the con-rod and crankshaft journal.
Con-Rod Bolts: High-torque bolts that secure the con-rod to the crankshaft.
Common Issues: Worn con-rod bearings (caused by oil contamination or lack of lubrication) can lead to a “knocking” noise from the engine—if left unaddressed, it can result in catastrophic failure (e.g., a broken con-rod piercing the engine block).
EPID Parts Support: We offer forged steel connecting rods (for WD618) and OEM-equivalent bearings (for all models). Our con-rod bolts are torque-rated to Sinotruk’s specifications, ensuring a secure fit and preventing (loosening) under load.
Maintaining a Sinotruk HOWO engine requires access to reliable, cost-effective parts—especially for fleet operators with hundreds of trucks. That’s where EPID Parts comes in. As a leading Chinese diesel engine parts supplier, we specialize in supporting major brands like Sinotruk HOWO, Weichai, Yuchai, Baudouin, and Cummins.
Our Expertise Covers:
Sinotruk HOWO: Complete coverage for WD615, WD618, and MC Series engines—from routine filters to core rebuild components.
Other Brands: We also supply parts for Weichai WP Series (truck engines), Yuchai YC Series (agricultural/marine), Baudouin M Series (gensets), and Cummins QSK Series (mining).
Quality You Can Trust: Our parts are tested to meet or exceed OEM specifications. For Sinotruk HOWO engines, we offer:
1. Genuine Parts: Sourced directly from Sinotruk (for MC Series).
OEM-Equivalent Parts: Manufactured to the same standards as genuine parts but at 20–40% lower cost (e.g., piston kits, cylinder liners).
2. Complete Overhaul Kits: Our Sinotruk HOWO Engine Overhaul Kits bundle all critical components (pistons, liners, gaskets, bearings) into one package. This simplifies the rebuild process, ensures component compatibility, and saves you time and money. For example, our WD615 overhaul kit includes:
6 forged aluminum pistons with rings
6 wet cylinder liners
Full gasket set (head, oil pan, valve cover)
Main and con-rod bearings
Valve train components (valves, springs, guides)
3. Our technical team is available 24/7 to answer questions and help you select the right parts.
Sinotruk HOWO engines are built to last, but their longevity depends on the quality of parts used in maintenance. For fleet operators and mechanics, EPID Parts offers the perfect balance of quality and affordability. Whether you’re replacing a worn piston in a WD615 or overhauling an MC13 engine, we have the parts you need—at a price that fits your budget.
Our OEM-equivalent parts deliver the same performance as genuine Sinotruk parts but without the premium price tag. And our complete overhaul kits make it easy to extend the life of your engine, reducing downtime and maximizing ROI.
For the most cost-effective, reliable Sinotruk HOWO engine parts—look no further than EPID Parts. We’re not just a supplier—we’re your partner in keeping China’s heavy-duty trucks moving.
Visit EPID Parts today to explore our Sinotruk HOWO parts lineup and experience the difference quality and value can make.
