The M gets the same 3.0-litre turbodiesel powerplant that we tried earlier this year in the EX. It produces 235bhp and 405lb ft, a decent enough pair of figures but shy of the outputs of the 530d, E350 and XF.
The hybrid version of the M, incidentally, is tipped by insiders to cost “only a modest amount more” than the diesel when it arrives in 2012.
See pics of the Infiniti M30d in action
What’s it like?
Well, this isn’t a car with the hard sporting edge of the 530d, or the waftability of the E-class. And the cabin doesn’t quite have the emotional connection of an XF’s, although fit and finish are excellent.
But if that sounds negative, it’s not meant to, because as an overall package, the M slips down between the cracks very effectively. The oil-burner has decent reserves low down, enough to make progress feel swift (but short of rapid).
You can rev it right through to beyond 5000rpm if you wish; doing so brings a note that fluctuates strangely between diesel rattle and sonorous V6. In truth, of course, there’s little point in thrashing it, because its best work is done by a little over 3000rpm. The seven-speed automatic gearbox isn’t particularly keen to be rushed anyway; even in sport mode, its shifts are smooth and relaxed.
It feels a heavy car, the M (it is, at 1840kg), but it’s well balanced enough and the steering has decent weight (if a little less feeling than we’d like). There’s enough there to deliver on the brand’s mission statement of a rewarding drive - just.
Inside the choice of materials is generally fine, and the refinement is excellent, particularly when cruising, when only a bit of wind noise will intrude. The non-S M30d rides on 18in wheels instead of 20-inchers, a factor that definitely reduces the amount of tyre rumble.
Should I buy one?
You shouldn’t rule it out. Yes, really. The M30d may be short of an absolute star turn - and we’re not sure if half of its standard toys will really tempt buyers away from the Germans - but there’s a well judged mechanical package here.
You should at least test an M30d if you’re in the market, because you may well conclude that it drives well enough. And from that point, you can start to weigh up the potential attractions of its extra standard kit.
Infiniti M30d GT Premium
Price: £44,600; Top speed: 155mph; 0-60mph: 6.9sec; Economy: 37.7mpg; CO2: 199g/km; Kerb weight: 1845kg; Engine: V6, 2993cc, turbodiesel; Power: 235bhp at 3750rpm; Torque: 405lb ft at 1750rpm; Gearbox: 7-spd auto
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