That equates to fuel efficiency ratings above 50mpg US (4.7L/100km) for all three cars in the range. The S40 and V50 DRIVe models yield 52.3mpg US (4.5L/100km) while the smaller C30 manages 53.4mpg US (4.4L/100km). All three cars are powered by the same 1.6L four-cylinder turbo-diesel engine.
Efficiency improvements are found all over the cars, first by improving aerodynamics. Lower chassis height offers a smaller frontal profile. Adding a front spoiler like that found on T5 models to the S40 and V50 enhances airflow as well. An improved grille, front-wheel wind deflectors, optimized wheel aerodynamics, underbody panels and a unique rear spoiler and rear bumper for the C30 complete the package.
Rolling resistance is lowered through the use of special Michelin tires, while higher gear ratios ensure the engine is turning at the lowest and most efficient RPMs possible. This step alone accounts for a 1.5% improvement in fuel efficiency. Finally, by improving engine cooling and minimizing parasitic loads from the power steering unit plus low-friction transmission oil, the driveline is made more efficient, so less energy is wasted as heat or friction.
The low emissions ratings ensure the cars will slot into the UK's Band B emissions profile, which is the next-to-lowest rating and offers more affordable yearly tax rates. There is no word yet regarding bringing the line to the U.S., but with the recent push among luxury carmakers toward diesel alternatives in the world's biggest car market, it is a real possibility.