New Bentley Bentayga Diesel 2017 review

Whether you love it or loathe it, the Bentayga is at its finest with a V8 diesel under the bonnet. It’s nearly as fast as the W12, far more economical and just as effortless when cruising, fitting in perfectly with the posh SUV’s character. It’s cheaper, too, although it’s still impossible to consider it good value for money. A Range Rover offers nearly as much capability and luxury for less, while if you can live without the badge and some of the sumptuous interior fittings an Audi SQ7 has the same astonishing powertrain and costs almost half as much.

A two-and-a-half tonne Bentley with a V8 engine that is capable of over 35mpg: that’s from the land of fantasy, right? Well, for the first time in the British carmaker’s history, one of its models has to be refuelled via the black pump, not the green one. That’s right, it’s a demonised diesel engine in front of the new ‘entry-level’ Bentayga SUV.

While the idea of an oil-burning Bentley may raise a few eyebrows, there’s a very good reason for buying a diesel Bentayga. Customers who opted for a W12 version are unlikely to worry about the financial burden of running something that barely musters 20mpg, nor are many likely to be that interested in the lower CO2 emissions. No, this car’s real selling point is that it’ll theoretically manage nearly 600 miles to a tank.

Compare that to the 12-cylinder car which, on a good day, might scrape 350 miles – and you can see the real allure. In theory, it means you’ll only have to deal with the undignified affair of refuelling twice on the journey to and from your ski chalet in the Alps, rather than four times in the W12.

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For those still sceptical about the idea of a diesel Bentley, they need only take a look at the facts and figures. It’s a 4.0 litre twin-turbo V8 with a 48v electric compressor to deliver 429bhp. More importantly, there’s a whopping 900Nm of torque on tap. That number is identical to the W12 model, and is delivered in full from just 1,000rpm. It’s mated exclusively to a four-wheel drive system and eight-speed automatic gearbox.

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If that sounds like the same engine found in Audi’s storming SQ7, that’s because it is. However, Bentley’s engineers claim it has been heavily recalibrated for use in the Bentayga, with the emphasis moved away from sportiness to refinement. It’s easily the most refined diesel engine we’ve ever encountered, staying fantastically hushed almost all of the time, and only emitting a distant V8 burble under hard acceleration.

Don’t think the quest for quietness has dampened its performance, though. Sprinting from 0-60mph in 4.6 seconds and hitting a top speed of 168mph, it stakes its claim as the fastest production diesel SUV on sale today. But its not the outright pace that impresses most. It’s uncannily relaxed in the way that it delivers its punch, rearing up and firing you relentlessly towards the horizon with only a touch of wind noise to inform you of your speed.

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Once you’ve become used to the effortless pace, you’ll find it’s impressively economical on a motorway cruise. We managed an indicated 36mpg on a 150-mile journey from Crewe to London, rarely finding the need for the revs rise past 1,500rpm – even when bringing it up to the speed limit.

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The new engine appears to have had little effect on the way the Bentayga rides and handles. For a near-2.5-tonne behemoth it’s impressively agile in the bends, with the clever Dynamic Ride electric anti-roll bars keeping the SUV remarkably level. It’s not a sports car, so there’s very little in terms of feel or engagement to be found in the drive, but it’s as agile as a Bentley 4x4 would ever need to be.

It’s decent off-road, too, with a ride height that can be raised and a plethora of Land Rover-style terrain control systems. It’s not quite as all-conquering as a Range Rover in the rough stuff, and the ride is slightly disappointing, too. It’s far from uncomfortable, but even in its softest setting it doesn’t smother surface intrusions quite as deftly as a Bentley should. Our car’s 21-inch wheels can take part of the blame, but they’re not even the biggest rims you can order.

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Of course, you still get the same divisive exterior look as the W12. You can decide whether you want a diesel badge or not, while the only other changes are new exhaust tips and specific wheel designs. The interior is also identical, with sumptuous, hand-finished leather and wood, and vast potential for customisation. Our car had a whopping £70,000 worth of options, in fact, and you can spend far more than that if you try hard enough. 

There’s one major flaw, however, and that’s the infotainment. It’s an older system than Audi uses in the Q7, looks very dated, and isn’t particularly intuitive to use. Given the extraordinary cost of our test car, we’d expect better, and it takes a little of the shine off what is otherwise a hugely capable and luxurious SUV.