Lots of power, a somewhat unusual exhaust gas purification system and the world's first dual-clutch gearbox for heavy-duty trucks are the striking features of the Volvo FH540.
In general, truck engines are among the fastest running out there. Even if the definition of low-, medium- and high-speed engines is not 100% clear, the D13K in the Volvo FH540 leans towards the medium-speed engines. Low-speed engines usually work at three- or low four-figure revs, and are overwhelmingly used in medium-sized freight or passenger ships.
The reason why the 12.8-liter, six-cylinder engine in the most powerful variant is not far from being a ship engine is partly to do with the engine characteristics. It delivers plenty of power down to 900 rpm, with the maximum torque of 2,600 Nm available just slightly above this. If needed, all 540 horses can be galloping away at just 1,450 rpm. Future engines from Volvo and other manufacturers will work at even lower revs than this D13K. Among the factors that make this possible here are the extremely high axle ratios, which keep the cruising revs down while still allowing for plenty of power in reserve when driving in top gear. The FH 540 runs at just 1,100 rpm when traveling at 85 km/h.