The right solution for tomorrow and the day after tomorrow

Without them, nothing would get to its destination: in Germany alone, trucks carry almost three quarters of all the goods transported and cover a total distance of 70 billion kilometers each year. And there’s still room to grow—experts predict that this figure will rise even further! With the indestructible power cell units (PCU)—consisting of the piston, piston pins, piston rings, and cylinder liners—MAHLE has created the right conditions to achieve this long-distance performance: thirty times around the earth and no wear and tear!

Diesel trucks remain prepared for heavy duty

In the future, there’ll be even more: according to a study, the quantity of goods to be transported in Germany will significantly increase again by 2030. Although electrification is also finding its way into commercial vehicles, the initial focus is on light urban distribution vehicles and city buses. Heavy-duty, long-distance hauling trucks still rely on the combustion engine.

The diesel engine of the future: cheaper, more cost-effective, and more reliable!

Alongside rising demand for high-performance diesel engines for trucks, the expectations placed on the units are also increasing! Trucks not only need to save fuel, but they also need to run for as long as possible and without any problems.

Over the decades, the MAHLE technologies for diesel engines have been constantly refined and optimized to make the trucks “cleaner.” Forty years ago, the fuel was injected with a mere 180 bar. Today the figure is 2,700: this means a much finer diesel distribution in the combustion chamber—with top precision and electronic operating map control for the optimum time of injection. The fuel thus burns much more efficiently at combustion chamber pressures of up to 250 bar.

Thirty times around the earth with six cylinders


The power cell units need to withstand this high cyclic pressure and the temperatures that occur during combustion: kilometer after kilometer, year after year. MAHLE experts therefore wanted to find out how a mileage of more than one million kilometers impacted a power cell unit. The “test specimen” was a trusty old Volvo truck and its six-cylinder turbocharged diesel engine with a displacement of 12.8 liters and a power output of 480 hp (353 kW). The heavyweight has already come a long way with this engine: it has a total of more than 1.2 million kilometers, almost 30 times around the earth, under its belt!

Load test passed—durability proven

The quality of the MAHLE components amazed even the developers themselves: “We measured the pistons, and we were pleasantly surprised: even after this long period of time, their tolerances were virtually indistinguishable from a new product,” stated Dr. Andreas Pfeifer, Head of Development Engine Systems and Components. The pistons weren’t the only parts that survived the prolonged stress without any difficulties. The other MAHLE components in the PCU also demonstrated high quality and durability—with no significant wear!

MAHLE solutions for the truck engines of tomorrow


The investigated piston comes from an engine that meets the current Euro IV standard with significantly stricter emissions limits. However, it is not just a case of complying with regulations. Lower fuel consumption is also necessary in order to reduce the total operating costs. “The critical aspect today is not only to implement individual measures for each component, but to ideally tune the complete system consisting of engine and peripherals,” stresses Dr. Andreas Pfeifer. Improvements to the engine mechanics will also off-load the oil circuit. The optimization then takes place across the engine. Efficiency and fuel consumption can thus be improved by up to three percent in total.

Many innovative steps toward a big goal

When designing new commercial vehicles, individual details must be developed in a consistent way. However, you also have to keep the truck as a “complete system” in mind! Matthias Fix and Dr. Andreas Pfeifer define the goal in this way: “We want to ensure that truck engines run reliably for even longer, require less fuel, and are less harmful to the environment. We are well on track with our systemic approach.”



We regularly provide technical tips relating to the powertrain, thermal management, and mechatronics in automobiles.


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