Integral to the enhanced fuel efficiency benefits are multiple optimized or new engine components. Low-friction cylinder improvements, including a redesigned piston and liner developed with smoother surfaces, and a clutched air compressor, which completely disengages the clutch from the engine, have been introduced in the 2014 engine models.

The advanced combustion technology of a new seven-hole injector offers better fuel atomization for a more even distribution of fuel within the cylinder, maximizing fuel efficiency and offering a greater savings for customers. A new crankcase ventilation system filters more oil from blowby gases before they leave the engine and at the same time improves engine backpressure for better performance.

Along with fuel efficiency improvements, design changes have been made to improve serviceability, such as the two-piece valve cover, which reduces repair time and is easier to handle than previous covers. Volvo removed lead from the valvetrain of its 2014 engines to reduce its environmental impact.

In addition to fuel efficiency improvements of up to 5% or more with the introduction of EPA ’10 engines with SCR technology, Volvo Trucks also delivers additional fuel efficiency through its XE—exceptional efficiency—powertrain package. Available on Volvo-powered VN highway tractors, the XE package boosts fuel efficiency by about three percent by lowering engine rpm at a given vehicle speed, a concept Volvo calls “downspeeding.” Possible through the combination of Volvo’s I-Shift automated manual transmission and a Volvo engine with modified software, XE allows the engine to cruise about 200 rpm less than the average truck sold today.

Fuel efficiency improves by about 1.5 percent for every 100 rpm of downspeeding, so customers spec’ing the XE package can expect up to a 3% improvement when compared with another overdrive transmission in a similar operation.