Driven: Peugeot 508 Hybrid4
The 508 HYbrid4 breaks that mould. It uses the same 161bhp diesel engine and 36bhp electric rear axle as the RXH, but without the chunky bodywork cladding and raised ride height of its closest relation. The emphasis is on making this the most efficient 508, and with one of the highest power outputs, too.
A combination of 95g/km CO2, four-wheel drive and staggeringly high efficiency will make the 508 Hybrid4 difficult to match in the D-segment and an attractive fleet option, helped by the UK government removing the 3% BiK surcharge for diesel hybrids earlier this year. It’s just a shame is that it couldn’t have withheld just one more gram of CO2, as this would’ve kept it in the second lowest banding when the BiK banding announced in year’s budget comes into effect in 2016.
Hybrid4 is a clever drivetrain, and very neatly packaged into the 508 saloon. The motor and battery are tucked away under the boot floor, and the only visual clue is a discreet grille badge. Interior changes are as subtle, with a hybrid display in the instrument binnacle and navigation screen and a power gauge which replaces the rev counter.
The drivetrain does come with a downside, though. Cramming the additional technology under the boot has resulted in a long but shallow luggage space. Drivers carrying deep boxes, for example, will have to put them on the back seat instead.
UK buyers will get a single trim level, based on the 508 Allure saloon. It’s well-equipped, with keyless entry and start, electrically adjustable heated leather front seats and Peugeot’s intuitive infotainment system with satellite navigation and Bluetooth connectivity.
There’s little to get used to. The car starts in its most efficient Auto mode, which uses diesel and electric power to return the most miserly fuel efficiency available, and it drives like a conventional automatic car with an overactive start/stop system. Economy can be boosted further by switching to ZEV pure electric mode at low speeds depending on battery charge, ideal for clawing back extra range at roundabouts.
The remaining 4WD and Power modes combine both power sources for an electric “boost” function or to provide extra grip as required. Those familiar with PSA’s ponderous electronically-operated manual will be glad to hear it’s much better here, with the electric motor cutting in to smooth the gaps between gear changes.
But, with an additional 140kg on board it’s not fast even with the extra power. Performance is brisk, but this is outpaced by the lesser-powered non-hybrid diesel. And that’s not its biggest problem.
At motorway speeds, the electric part of the drivetrain is usually dead weight. There’s no ability to decouple the engine, as some hybrids can, at high speeds to “sail” on electric power and this puts a dent in its fuel efficiency. Drivers expecting close to the claimed 78.5mpg could feel short-changed at the more realistic mid 50s to the gallon offered on long distance trips – not worlds apart from the 2.0 HDI 163.
There’s a knack to getting the best efficiency. Use the ZEV mode as often as possible and knock it into AWD to let the electric motor assist the diesel engine and gentle driving will give an uplift in economy. But not by loads. With plentiful rivals on the way, it’ll be interesting to see if Peugeot alters this during a mid-life refresh, which will make the technology genuinely advantageous for motorway drivers.
The 508 Hybrid4 saloon may struggle to achieve its on-paper efficiency figures, but it offers gutsy performance and grip for the UK’s unpredictable winters without being a big polluter or expensive to tax. Drivers regularly using long stretches of motorway may find the 2.0 HDI 163 a more suitable option.
Segment: Upper medium
Type: Diesel-electric hybrid
Electric range: <1 mile
CO2 emissions (tailpipe): 95g/km