Test Car Specifications
Model tested: BMW M5
Price: £89,640 on-the-road
Engine: 4.4-litre twin-turbocharged V8 petrol
Transmission: eight-speed automatic, four-wheel drive
Body style: four-door saloon
Top speed: 155mph (limiter can be raised to 190mph with optional M Driver's Package)
0-62mph: 3.4 seconds
Power: 600hp at 5,600-6,700rpm
Torque: 750Nm at 1,800-5,600rpm
Kerb weight: 1,855kg
Power-to-weight ratio: 323hp/tonne
What's this?
The 2018 BMW M5, the sixth in a line of sports saloons that stretches back to the E28 model of 1984. And my how things evolve. The new car is the first M5 to feature an all-wheel-drive system, called M xDrive, and it's a bit special. At the rear is the usual Active M Differential that can split its input in any percentage necessary to either of the back wheels, varying locking from zero to 100 per cent. For the M5, it has been improved by the introduction of carbon plates and new control logic. On the front axle, meanwhile, is an open differential. Splitting engine output between front and rear is a transfer case housing an electromechanically activated multi-plate clutch that changes the split depending on driving mode, road conditions and other sensor data. All of this is overseen by a brand-new driving dynamics control unit, which communicates directly with the Dynamic Stability Control (DSC).
But there are no target splits front-to-rear, as such, as BMW M describes the strategy as 'feed forward' instead, the end result being how the car drives. From the driver's point of view, there's the 4WD mode by default, which is quite neutral, then 4WD Sport in conjunction with a mid-setting of the DSC called M Dynamic mode, which has the aim of sending more power to the rear wheels more of the time, unless more traction is required. Finally, the driver can turn off the DSC completely and then choose 4WD, 4WD Sport or 2WD.
Power comes from an upgraded 4.4-litre V8 using a pair of new turbochargers and higher fuel injection pressure than the previous BMW M5. It's bolted to an eight-speed automatic transmission with three levels of Drivelogic to choose from and a chunky new shift knob, plus the usual gearchange paddles behind the steering wheel. Peak power is quoted as 600hp, while torque is now 750Nm (up 70Nm on the car it replaces), available from just 1,800rpm all the way around to 5,600rpm. The lubrication system has been enhanced too and it features a map-controlled oil pump that is claimed to be up to the rigours of use on a race circuit. The exhaust manifolds have been optimised further and even the dual-brand exhaust is lighter than before. That features a variable flap that opens depending on the engine mode, while the driver can choose to 'soften' its noise too with a dedicated button.
That's one of several bespoke pieces of switchgear inside the cabin, found on the centre console along with those for the engine, steering, damping, DSC and a large 'SETUP' button for quick access to the iDrive sub-menu controlling the M xDrive settings. As we've become accustomed to, it's possible to group your favourite combination of modes under the M1 and M2 options, and they're now accessed by bright red buttons sticking out of the steering wheel. They're complemented by a bright red engine start button and a unique look for the digital dashboard, which also features shift-up' lights for when you decide to change gears for yourself. There's also a lovely new (still round) leather steering wheel and gorgeous M seats. Overall, it looks pleasingly different to the cabin of a regular 5 Series inside.
Same story on the outside thanks to a new carbon fibre roof, wider track, deep bumpers and side sills, plus the usual BMW M signifiers such as unique door mirrors and four exhaust outlets. The wheels are 20-inch items as standard, too, and there's a subtle boot spoiler to complement the aerodynamic diffuser underneath.
How does it drive?
As much fun as the previous BMW M5 was to drive on track, it never felt like its natural habitat. Capable as it was, you learned that over time rather than through its communication. And it undoubtedly had the ability to scare the uninitiated when the road surface was anything other than dry. The new car eliminates all of that. While we'd still suggest that that steering could be more talkative, the rest of the chassis is spot on and it feels more capable in a wider range of scenarios than before, as well, depending on your drive settings. So, it does the long distance cruising on the motorway thing comfortably and effortlessly for a start and it's a complete hoot when the road turns twisty, belying its size by attacking tight corners and quick direction changes with real gumption. The steering might not tell you much about grip levels at the front tyres, but it's beautifully weighted.
The damping is phenomenally controlled too, even over less than perfect surfaces, giving you the confidence to push the M5 on where you might have hesitated in the old car. Assisting with that confidence is the new version's ability to telegraph to the driver how much traction is available to a fine degree. BMW M's engineers put that down to the upgraded Active M Differential. Whatever it is, it's uncannily easy now to sense when it's time for a little circumspection with the razor-sharp throttle (it's smoother and 'duller' in Comfort mode). Saying that, the M xDrive system gives the new car outstanding traction so you need to be trying pretty hard to lose any. Strictly speaking, there's no need for the conservative standard 4WD mode on a dry road, but neither is it necessary to switch into the 2WD setting (with no DSC back-up, remember) to get your thrills, as the middle setting, 4WD Sport, is very well-judged. My suggestion to keen drivers is to turn DSC off and then select 4WD Sport, as it allows more slip at the rear axle than you'll ever really want on a public road, allowing you exploit the chassis to the full, have a lot of fun and yet carry huge speeds out of corners thanks to the gentle assistance of the front wheels. It's highly effective and importantly, lots of fun, even when you're not breaking the speed limit. This M5 really is a revelation in terms of what can be done with four-wheel drive in the name of driving enjoyment
Our focus here is on the chassis, unsurprisingly, but rest assured that the V8 engine is just as special, and unnervingly torque-rich across a wide band of the rev counter, giving it massive performance whether you're unnecessarily chasing the redline in each gear or short-shifting and riding that torque. It's perhaps not as tuneful as some V8s on the market, but it certainly sounds purposeful. As ever with BMW's automatic transmissions, the eight-speed system (a torque converter unit, replacing the old dual-clutch gearbox) is nigh-on perfect, managing smooth and cultured normal driving at one end of the scale and lightning-quick up- and down-changes at the other, with full manual control always there for the taking.
Verdict
If you're one of those cynics referred to at the top of the page, unhappy with the fact that the BMW M5 now has all-wheel drive, and you're still not convinced by this review, you really need to get behind the wheel of the M5 for yourself, as it's a peach. The M xDrive system is brilliantly thought out and implemented; mixed with other worthwhile upgrades throughout the car, it helps make this model one of the most broadly capable and engaging M5s yet made. Sweet.
Exterior Design
Interior Ambience
Passenger Space
Luggage Space
Safety
Comfort
Driving Dynamics
Powertrain
