Mercedes ML 63 AMG (2012) first pictures

Mercedes is packing its M-class off-roader off to the gym to beef up to BMW's M division SUVs and Porsche's Cayenne Turbo. The result? The new ML63 AMG, unveiled today.

The new high-performance ML63 packs AMG's new 5.5-litre V8. They call it downsizing, but shrinking from 6.2 litres to 5.5 hardly compromises the outputs: the bi-turbo V8 cranks out 518bhp and 516lb ft.

Depending on your perspective! One man's go-faster SUV is another man's dream car, and all that.

If you like fast 4x4s, you'll love the ML63. It gets 15bhp and 52lb ft over the outgoing AMG'ed M. And if you spec the AMG Performance pack and its swollen 1.3 bar boost (up from 1.0), the outputs grow to 549bhp and 561lb ft. These are truly startling figures for a big, bluff 4x4 - these big luxury sports utility vehicles have a unique feel from behind the wheel when you stamp on the gas.

Merc's newcomer will become one of the fastest yet. Although limited to 155mph, the ML63 will pass 62mph in just 4.8sec (knock a tenth off that if you spec the Performance upgrade). This is knocking on the door of supercar territory.

To ease your conscience, Mercedes has fitted a smattering of fuel-saving tech to the new 2012 ML63. There's stop-start, the latest piezo-managed direct injection and a seven-speed auto transmission for a CO2 rating that's down from the previous highs, at 276g/km. The AMG is 40kg lighter than its predecessor, too - helping trim average economy to 23.9mpg.

AMG chairman Ola Källenius acknowledges that the new ML63 has had to do its bit for the environment. 'Like its predecessors, the new ML63 AMG sets new standards in terms of performance, exclusivity and a superlative driving experience – plus the efficiency factor, which is acquiring ever greater emphasis at Mercedes-AMG.'

Källenius also points out that it was Mercedes who invented this niche, with 1999's ML 55 AMG (packing a then-eye-popping 342bhp from its 5500cc V8). The new chapter opens in spring 2012; UK pricing is yet to be confirmed.

Four-wheel drive, Airmatic air suspension with three selectable modes, adaptive dampers and a choice of 20in or 21in alloys. There's even a line in the brochure with a lot of ticks alongside the kitchen sink.

If you wonder why Merc persists with such high-powered SUVs, consider this. It sold 13,000 ML63 AMGs in the last generation between 2006 and 2011. Since the 1990s, it's flogged 24,000 in total. So even if many CAR Online public commentators get stuck into big-bhp off-roaders, remember there is a demand out there somewhere. Probably in the Middle East, Russia and Asia, we suspect

By Tim Pollard