Some will immediately dismiss the 2018 BMW M5 as sacrilegious because it switches from rear-wheel drive to all-wheel drive for the first time ever in the illustrious nameplate's history. They should try out the very special new M xDrive system themselves before making a hasty judgement, as our drive in a prototype version reveals that it makes the new M5 a better and still more enjoyable sports saloon to drive than ever before.
Test Car Specifications
Model tested: 2018 BMW M5 pre-production prototype Pricing: under £80,000 estimated Engine: 4.4-litre twin-turbocharged V8 petrol Transmission: all-wheel drive, eight-speed automatic Body style: four-door saloon CO2 emissions: 241g/km Combined economy: 26.9mpg Top speed: 155mph (limited, 189mph limiter optional) 0-62mph: 3.4 seconds Power: 600hp at 5,600- to 6,700rpm (estimated) Torque: 750Nm from 1,800- to 5,600rpm (estimated)
What's this?
Our first taste of the 2018 BMW M5; and the big news is that it'll feature four-wheel drive for the first time in the nameplate's now six-generation history. BMW calls it M xDrive and it has a lot of promise. The mechanical bits include an updated Active M Differential at the back that can apportion output to the rear wheels in any split whatsoever; a transfer case in the middle that uses an electromechanically activated multi-plate clutch to divide torque between the front and rear axles (again to any percentage whatsoever, from fully front-wheel drive to fully rear-wheel drive); and the use of a new development of the company's eight-speed automatic transmission in place of the old dual-clutch M DCT. Controlling all that is a new in-house programmed brain, which also works with the Dynamic Stability Control (DSC) system. The target is a real M car driving experience, but with a much wider breadth of capability, especially when it comes to less than perfect weather.
By default, the DSC system is on and M xDrive is simply in '4WD' mode. Pressing the DSC button briefly activates M Dynamic Mode (MDM) and 4WD Sport for the xDrive, while the driver can choose between those two xDrive settings and full-on 2WD if they hold down the DSC button long enough to disable it completely.
Under the bonnet is an updated version of the previous M5's twin-turbocharged 4.4-litre V8, putting out 600hp and 750Nm, with a claimed 0-62mph time of 3.4 seconds.
The interior of the prototype was covered up for the most part, but the usual M trinkets are present and correct, including a lovely new steering wheel with repositioned M1 and M2 buttons, gorgeous bucket seats trimmed in leather and a chunky new gear selector with the Drivelogic toggle switch built in. The instruments have been restyled too and the centre console is a little different to that of the regular 5 Series.
How does it drive?
We're going to focus mostly on the xDrive system here, as details about the rest of the car are scant and we only tested the M5 on track. First up was a few laps of a high-speed circuit on a damp, but slowly drying track, following a BMW M4 GTS driven by none other than Timo Glock, one of BMW's works DTM race drivers. He wasn't hanging about, but the M5 made it relatively easy to hang on to his tail thanks to the lusty V8 of course, but also the traction afforded by the chassis. In 4WD mode with the DSC turned on, progress is swift and effortless, and very safe. The DSC kicks in early, reacting quickly to changes in grip level, though it's so smooth that the only tell-tale is the orange light flickering in the dashboard. This set-up will be great for everyday use in all conditions on the road.
Moving into the MDM and 4WD Sport setting, the M5 feels much more like you'd expect a car with that badge to. More power is sent to the rear axle by default and it undoubtedly feels like a rear-wheel-drive car to start with. Only when you considerably exceed the grip levels of the rear tyres do you detect a smooth transition of torque to the front axle, but you need to be trying pretty hard to get to that stage, and the DSC system allows a gratifying amount of slip too, which is enough to get a bit of a thrill from the car without relying completely on your own skill level. This is the setting keener drivers are likely to use most of the time, even on the public road.
We'd expect only the more experienced to turn off the DSC completely, but it can be done without any fear, as our test on a soaking wet handling circuit revealed. There's a huge amount of traction and grip and the new M5 really does telegraph its limits remarkably well, whether the surface underneath is wet or dry. In 4WD mode it still grips and behaves relatively neutrally. Indeed, if you want to slide it about in this setting then you really have to provoke it. The 4WD Sport mode is rather different, as the car can easily be coaxed into a controllable, yet lurid looking, power slide at will. It's huge fun in the right conditions and it's possible to push things very far and still recover the slide. That's probably partly to do with the new electrically assisted power steering system, which is more direct than before, but also, reckons BMW M's engineers, the revised Active M Differential. Whatever they've done, it's simply brilliant.
And the controllability of the base chassis is underlined when you switch it into 2WD mode and tackle the same piece of track at the same speed. Sure, it goes more sideways quicker if you want it to and you need to be ready with the opposite lock sooner, but it's still relatively friendly to drive fast in wet conditions. Bodes very well indeed for the final product when it arrives in the UK early next year.
Verdict
Now, we have not yet driven the new BMW M5 on the public road, we don't yet know all its technical specifications and it may turn out quite expensive, but one thing we can categorically state is that the new M xDrive four-wheel-drive system enhances the driving experience no end, potentially helping the M division create the best M5 yet.