BMW X5 review - how does it compare to the Porsche Cayenne? - Engine and gearbox

BMW’s original SUV is still its best, still handling like a big 5-series. It’s just a shame it means so much less today…

Evo rating
Price
from £57,495
  • Exceptional drivetrains, build quality and refinement. M50d stonking, yet more sensible than most fast SUVs
  • Overall handling is capable, but benign. Anything but subtle, but then an X5 never really was

Engine and gearbox 

Diesel engines may be about as popular as acid-wash jeans right about now, but when talking about a reasonably sensible two ton-plus SUV, petrols and hybrids still have a way to go before becoming the engine of choice. As a result, it’s not surprising to see that BMW has placed the biggest emphasis on its 30d and 50d power units, with a sole 40i petrol offered just for those who really don’t like acid-wash.

We drove both diesels on test, and found them to be impressively hushed and flexible throughout the rev range. The 30d’s 261bhp is impressive enough, but it’s the torque that keeps the hulking great body moving with plenty of vigour. It’s not exactly brisk, but it never feels underpowered, like it wouldn’t be hampered by a full load or trailer on the back. The engine’s calibration with the eight-speed ZF gearbox is also very impressive, mooching seamlessly between gears, without any of the hesitation that so often inhibits smooth and urgent progress in modern diesels.

Subscribe to evo magazine

Subscribe today to have every issue of evo delivered straight to you. You'll SAVE 39% on the shop price, and get evo for its original cover price for a whole year!

It’s the M50d that steals all the headlines here though, with its quad-turbocharged 3-litre straight-six that produces those impressive power and torque figures. Layed out as two separate sequential twin-turbo systems, the journey of compressed air within the M50d’s engine bay is about as convoluted and confusing as Alice’s in Wonderland. At low rpm the first two small turbochargers quickly spool to spike the torque curve as quickly as possible. Then, at around 2000rpm, the larger turbos begin to spin, taking over from the smaller units right up to around 4500rpm, when the torque and power start to drop off their plateau.

Although it sounds massively convoluted, from inside it’s nearly intangible that so much is happening in front of you, rather you just feel a great surge of power. Unfortunately, BMW’s M Performance department has decided that a bit of M5-style sound generation is also required when set in Dynamic mode, masking the engine’s not entirely unpleasant sound by overlaying it with fake noise pumped in from somewhere around your right knee. This is not well executed, or indeed necessary, as from outside the X5 M50d sounds surprisingly edgy, in a big-diesel kind of way. What the M50d does is straddle the line between a sensible SUV engine option (if there ever was one) and the mad petrol-powered flagships that seem to make no sense outside of major British Petroleum shareholders.

Most Popular

Hyundai i20 N revealed – 200bhp supermini ready for some Ford Fiesta ST baiting
Hyundai i20 hatchback

Hyundai i20 N revealed – 200bhp supermini ready for some Ford Fiesta ST baiting

Long-awaited second N division model set to shake up the junior hot hatch establishment
20 Oct 2020
£153,000 ​Alfa Romeo Giulia GTA enters final stages of development
Alfa Romeo Giulia Quadrifoglio

£153,000 ​Alfa Romeo Giulia GTA enters final stages of development

Alfa Romeo has put its F1 drivers behind the wheel of the Giulia GTA and GTAm ahead of production in 2021
20 Oct 2020
Volkswagen Golf GTI 2020 review – eight generations new, the GTI still has the goods
Volkswagen Golf GTI

Volkswagen Golf GTI 2020 review – eight generations new, the GTI still has the goods

A very good hot hatch, but a great Golf GTI, the new mk8 excels where required to form a very desirable offering
19 Oct 2020
SSC Tuatara hypercar hits 331mph, making it the world’s fastest production car
News

SSC Tuatara hypercar hits 331mph, making it the world’s fastest production car

Over a decade after SSC last entered the record books, its Tuatara has claimed the title of world’s fastest production car
19 Oct 2020