After our test of the X6 M50d, we 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 X6M and its biturbo-petrol V8.
The 3,0-litre six-cylinder turbodiesel is part of BMWs M Performance sub-brand (which slots in between normal models and full-fat M vehicles). Only the upcoming X5 M50d and this X6 will be sold in SA, as the 5 Series with this engine is not available in RHD.
The engine employs compound turbocharging that 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 6,01 seconds. It steam rolls from 100 to 140 km/h in a mere 4,79 seconds thanks in no part to a smooth eight-speed ZF transmission, smashes the kilometre marker after 25,8 seconds, and tops out at 250 km/h. Performance-wise, it deserves the M moniker. In terms of fuel economy, however, it beats all other Ms; 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, 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 engine unfortunately can’t hide is the X6’s compromised underpinnings. A vehicle weighing 2 360 kg will never feel nimble and however much the M50d tries its best to provide some fun, it delivers very little driver enjoyment. The steering is heavy and dead, the enormous 315/35 R20 rear tyres grip well but the fronts relinquish traction too early and the ride is very firm.
The rest of the X6 experience is per usual. If you like the concept, things like tight rear headroom, an aging cabin, smallish SUV boot and aesthetically challenging looks won’t matter. We’re not convinced, however.
Test Summary
At R1,1 million, the X6 M50d makes much more sense than the X6M at R1,45 million. It’s almost as quick and uses much less fuel. That doesn’t make it a great car, though. We’d wait for the new and far more practical X5 M50d, stick to the X6 xDrive40d (R880 503) or, better yet, place an order for a Porsche Cayenne S Diesel and spend R120 000 on extras.