The world’s plushest MPV has almost completed its strip-tease, revealing the sleek lines of Mercedes-Benz’s production R-class.

Shown as a concept four times, the MPV is undergoing final testing ahead of European sales a year from now. Prices are still up in the air, but expect them to kick off at about £40k.

Benz’s US plant in Tuscaloosa, Alabama will build the R alongside the new M- and G-classes. The R shares much of its underpinnings with the two off-roaders, including suspension and four-wheel-drive system. Likewise, it will be built in two sizes. The standard car, aimed at Europe, is 4,922mm long, while the US-biased XXL version measures around the same length as an S-class at 5,150mm.

Mercedes will sell both sizes in Europe, with the same 4+2 seating arrangement. However, the bigger car has an extra 235mm between the wheels, transforming the rear perches from occasional use to adult-acceptable. Optional twin sun- roofs keep the cabin airy, although the sloping roofline restricts headroom for the back row.

Sources say there will be no middle bench option, so those two passengers can luxuriate in captain’s chairs with plenty of shoulder room. Both rows of seats fold flat, transforming luggage capacity from a tight 200 litres to 1,800 litres.

V6 and V8 engines provide the power, including two fresh V6s: the 272bhp 3.5-litre petrol introduced in the SLK MkII, and an all-new common-rail diesel.

This 3.0-litre unit kicks out 224bhp and 376lb-ft. The bent eight line-up includes a 320bhp 4.0-litre V8 oilburner and a 306bhp 5.0-litre petrol. The AMG version is tipped to run a 500bhp-plus 6.3-litre.

Power will be sent to all four wheels via a seven-speed automatic transmission, with the gear selector mounted on the steering column. Concept car-sized 19in wheels will be offered, but the ride is cosseted with Airmatic air suspension.

DESIGN

It’s an MPV but not as we know it, with rakish roofline, coupe-esque glasshouse and bold details.

CHASSIS

Chassis shared with Merc’s new off-roaders, which means air springs and permanent four-wheel drive.

ENGINES

V6, V8 petrol and diesel engines, including punchy 272bhp V6 petrol and new 3.0-litre oilburner, kicking out 224bhp.