BMW's engine range for the X5 primarily focuses on diesel units and comprises the 25d, 30d, 40d and 50d. All but the 50d, which displaces 3.0 litres, are 2.0-litre engines.
A 4.4-litre twin-turbocharged petrol V8 is also offered in 50i variants, for those seeking the most refined of the X5s. To date we've only tested the 30d, 50d and 50i.
The 3.0-litre diesel variant of the new X5 is much improved compared to its predecessor, its clatter and growl usurped by a subtle background hum. Lots of low-rev urge and the eight-speed auto gearbox’s excellent anticipatory skills make for authoritatively brisk and effortless performance that, at lower speeds, shades the petrol 50i for easily accessed power.
The 50i provides a 4.4-litre V8 coupled to an eight-speed paddle-shift transmission. It’s an engine familiar from the last X5, now with a sharper performance and economy mix. Power climbs 10 per cent from 401bhp to 444bhp while torque rises 37lb ft to 479lb ft to shave half a second from the 0-62mph time, which falls to 5.0sec. Economy improves a little, too.
Yet despite this potency, and the traction to make good use of it, this ultimate petrol X5 is not the fastest thing off the line. Engine and transmission need a frustrating few moments to absorb your commands before launching the BMW with the power you’d desired moments earlier.