How many turbos are too many? BMW would argue that three is just enough. We recently had the X6 M50d on test and were left perplexed about its role in the BMW range, whether it’s dynamically capable and exciting enough to wear an M badge (it is after all the first oil-burner to wear the tri-colour M) and where its presence in the range leaves the significantly pricier flagship X6M.
The 3,0-litre six-cylinder turbodiesel features in 50d guise in four BMWs – the X5, 5 Series sedan and Touring and the model we tested – as part of BMWs M Performance sub-brand (which in effect slots in between the normal models and full-fat M vehicles). Only the SUVs will be sold in South Africa, as the 5 Series cannot be engineered with the steering on the right-hand side when fitted with this engine and the company’s all-wheel-drive system.
Developing a staggering 280 kW and 740 N.m (a whole 100 N.m more than the X6M), the engine employs compound turbocharging. This system uses a single small turbo at low engine speeds, a larger, low-pressure turbo that delivers air to the inlet side of the first turbo and a third one that’s also small and boosts performance at high engine speeds.
The result is a tested 0-100 km/h acceleration figure of only 5,8 seconds. It steam rolls from 100 to 140 km/h in a mere 4,7 seconds thanks in no part to a very smooth eight-speed ZF transmission, smashes the kilometre marker after 25,8 seconds and tops out at a claimed 250 km/h. Performance-wise, it certainly deserves the M moniker. In terms of fuel economy, however, it beats them all; on our varied-use fuel run, it used a mere 8,4 litres/100 km.
The engine also sounds unlike any diesel we’ve tested. At idle and low engine speeds, its black heart is obvious as it rumbles and groans, but get it above 2 500 r/min and it starts to sound like an old-school V8 as it revs freely to the 5 400 r/min red line. It isn’t a sonorous noise, but it certainly sounds purposeful thanks to BMW’s extensive acoustic tuning.
What this magnificent engine unfortunately can’t accomplish is hide the X6’s compromised underpinnings. A vehicle weighing 2 360 kg will never feel nimble or corner-hungry, and however much the M50d tries its best to provide some fun, it ultimately delivers very little driver enjoyment. The steering is too heavy and dead, the enormous 315/35 R20 tyres at the back grip well but the front ones relinquish traction too early and the ride is unrelentingly firm.
The rest of the X6 experience is as usual. If you like the concept, things like tight rear headroom, an ageing cabin, smaller-than-average-for-an-SUV boot and aesthetically challenging looks won’t matter. We’re not convinced, however.
At R1,1 million, the X6 M50d makes much more sense than the X6M at R1,45 million. It’s almost as quick, uses less fuel, is very well equipped and has a very charming drivetrain. That doesn’t make it a great car, though, or one worthy of an M badge. We’d opt for the far more practical X5 M50d at R990 000, stick to the X6 xDrive40d (225 kW, 600 N.m and R880 000) or, better yet, place an order on the V8-powered Porsche Cayenne S Diesel and spend R250 000 on extras.
FAST FACTS
Model: BMW X6 M50d
Engine: 3,0-litre, six-cylinder, triturbo-diesel
Power: 280 kW at 4 000-4 400 r/min
Torque: 740 N.m between 2 000 and 3 000 r/min
0-100 km/h: 5,8 secs
Top speed: 250 km/h
Fuel-run consumption: 8,4 L/100 km
CO2: 204 g/km
Price: R1 097 118
Maintenance plan: 5 years/100 000 km
