BMW M5 vs BMW 6 Series

What's the difference?

The term bigger is better doesn't often apply to performance cars, but it fits the M5 Competition perfectly. Big inside, but small outside when it matters, BMW's new performance flagship might be expensive, but there's no shortage of bang for those bucks.

This isn't a car for everyone's tastes, but if you fit in to the buyer group that just doesn't really know what they want in a luxury car, it could be the perfect fit for your family. The 6 Series GT is a practical large prestige car, albeit one that will likely find very few buyers.

Let’s start with the new stuff, shall we? The BMW M5 Competition gets a new colour ('Frozen Dark Silver'), as well as new 20-inch (and lightweight) alloy wheel designs, and the grille, aero-designed wing mirrors and boot lip are finished in high-gloss black. The quad exhaust pipes are a black, too, as is the rear diffuser. Elsewhere outside, though, it’s the more muscular 5 Series of old.

Parked next to the much smaller M2, you quickly realise just how much bulk the M5 is carrying. It stretches 4966mm in length and 1903mm in width, and it looks every centimetre of those dimensions in the metal.

Climb inside, and you’re greeted with the familiar BMW interior design, with a huge centre screen, digital driver’s binnacle and a spaceship-level number of buttons surrounding the shift lever. The M5 Competition also arrives with full leather (seats and dash) trim, with carbon-effect dash inserts and aluminium pedal and foot rest trims.

Is it the most adventurous design treatment, inside or out, that we’ve ever seen? Well, no. But it looks polished and premium outside, and feels plenty comfortable inside.

There is no denying the 6 Series GT looks better than the old 5 Series GT. It isn't as frumpy, it looks more sporty, and to me it appears to have grown into its identity with more conviction than its predecessor.

That said, I don't necessarily like the look very much - it's a bit like a BMW X6 that has been rounded off a little and lowered down substantially. But I can appreciate some of the finer design aesthetics that it offers up: the frameless windows are a nice touch, and the swooping roofline looks smoother than a duck's back.

Other things like the active grille shutters and the air breathers ahead of the front doors are nice functional touches, and to my eye it lives up to BMW's hope of it looking "smooth but muscular". You can get the 630i with either the M Sport package, like you see here, or the more sedate Luxury Line, which is, well, more luxurious looking.

The M Sport styling and equipment package you see in the images here - with M aero kit and 19-inch wheels (ours had been upgraded to optional 20s) - help out with the athletic look of this very big vehicle.

It's huge in fact. The length of the 630i is 5091mm long, it measures 1902mm wide and sits at 1538mm tall, with a lengthy 3070mm wheelbase.

All that equates to a lot of room in the cabin, and what a sumptuous and delightful place it is to be - leather, wood and plush finishes abound.

As far as performance cars go, the M5 Competition is a rolling Swiss Army Knife. For one, it’s bloody massive, which pays considerable dividends for passengers. 

Up-front, the seats are far enough apart to ensure you’ll be rubbing shoulders with exactly nobody. The centre console Is super wide (all the better for fitting all those buttons), allowing for a sizeable centre storage bin, joined by two cupholders and a second storage bin in front of the shifter which is also home to your USB, power and 'aux-in' connections.

In the back, there’s business-class levels of leg and headroom, and you can even fit another whole adult in the centre seat if you’re so inclined. The pull-down seat divider is home to two extra cupholders, sitting in front of a thick armrest, and the rear air vents get their own temperature controls. There’s an ISOFIX attachment point in each window seat, too. Pop the capacious boot and you’ll find 530 litres of storage space.

Now, I said before that this is a bit like an X6, but it has heaps better interior space than that SUV.

As soon as you slide into the driver's seat, you feel like your inside a large car. The cabin space is plentiful, and there's an abundance of storage on offer, too: there's a split-lid armrest between the seats, a pair of cupholders, a phone storage nook with wireless charging, and big door pockets with bottle holsters.

In the back you have access to door pockets, a flip-down armrest with cupholders (that middle part of the seat can fold down completely to allow storage of longer items), and there's excellent room on offer. How many seats in the BMW 6 Series GT? Five - like, five full-size seats.

Because the roofline doesn't rake as sharply as a four-door 'coupe', headroom is excellent for adults (even of the 183cm variety, like myself), and legroom and toe room are equally very good. This is bigger in the back than a 5 Series, but maybe not as plush as a 7 Series… so I guess it makes sense numerically for its nomenclature.

Of course you get climate control in the front (and in the rear if you option it), and the materials are excellent. The media screen is tablet-style, proudly displaying 10.25 inches of high-def real estate that is both touch-capacitive and controllable by way of the central rotary controller with touchpad. And get this - you can even use gestures to control certain elements like volume, swiping and changing tracks… but you have to option that.

The fully digital instrument display is bordered by a set of incomplete dial rings, which is just odd. BMW, back yourself - your buyers can handle just having a digital screen in front of them, particularly when it's as good as this one.

This grandiose hatchback's boot is commodious - with the back seats in place it has a huge 610 litres of cargo capacity, which extends to 1800L with the 40/20/40 seats folded down using the quick release levers in the boot area.

There is no spare wheel (the BMW range is fitted with run-flat tyres) but it does have a secondary hidden storage area under the boot floor for hiding items or stowing wet gear, bathers/swimmers or muddy clothes.

For context, the X6 has 580L seats up, 1525L seats down.

The BMW 6 Series Gran Turismo range starts off with the model tested here, the 630i. It has a list price of $123,500 before on-road costs - and that's whether you buy the M Sport Line or the Luxury Line.

That's quite a lot of money. And while it has a lot of equipment to help justify the cost, the smarter dollars will probably find their way to a more affordable 5 Series.

Standard gear in this spec includes adaptive air suspension with multiple drive modes, a colour head-up display, semi-autonomous parking, adaptive cruise control with steering assistance, auto high-beam LED headlights with LED daytime running lights, DAB+ digital radio, a 16-speaker harman/kardon sound system, a 12.3-inch driver information screen and a 10.25-inch media display with sat nav, Bluetooth and 'BMW ConnectedDrive' online services.

Hey, you even get a panoramic sunroof as standard! Plus there are things like an active rear spoiler, two USB ports and four 12-volt outlets, leather trim, heated front electric seats, electric steering wheel adjustment, keyless entry, push-button start, and an automatic boot.

It also comes loaded with active safety assistance functions - we'll get to that in the safety section below.

Things it's missing at this price point? Well, heated seats are an option, but bundled nicely into the 'Comfort Package' ($3000) which was fitted to our car. The pack includes heated seats front and rear, quad-zone climate control, electric sunblinds for the rear side windows, and electric seat back adjustment. Oh, and BMW continues to gouge consumers $623 for Apple CarPlay (which seemingly didn't work in our car).

The only other 6 Series GT model available is the 640i xDrive, which is again available with the choice of M Sport or Luxury body styling. It's also pretty exxy, with a list price of $148,900, but gets a more performance-focused drivetrain, as well as extra equipment: essentially the Comfort package, plus vented front seats, interior fragrance (eight options), memory settings for the front seats, 20-inch wheels and metallic paint.

Plus the 640i has Sport+ settings - it's probably the wrong car for those - and 'Integral Active Steering' to couple with the all-wheel drive system.

Yes, our all-electric future feels inevitable. And yes, there’s much fun and performance to be had from battery-powered EVs. But you can’t help but hope that future is a Star Wars style far, far away when you get acquainted with the BMW M5 Competition’s monstrous twin-turbo V8.

It’s good for a wondrous 460kW (up 19kW on the regular M5) and 750Nm. Both of which are big numbers, which are fed to all four wheels via an eight-speed 'M Steptronic' automatic. Happily, you can, at the push of some buttons, make the M5 a rear-driver again. It’s slower, but damn if it ain’t much more fun.

As a result, the performance numbers need to be seen (or better yet; felt) to be believed. The near-two-tonne M5 Competition will blaze from 0-100km/h in 3.3secs, 0-200km/h in 10.8secs, and push on to a limited top speed of 250km/h (or 305km/h, provided you do some BMW driver training).

Under the bonnet of the 630i is a 2.0-litre four-cylinder turbocharged petrol engine, which produces 190kW of power (at 6500rpm) and 400Nm of torque (from 1550-4400rpm). It uses an eight-speed automatic transmission, and is rear-wheel drive.

That may not seem a lot considering the size of this machine, but consider that some of the steamiest four-cylinder hot hatches have nearly the same outputs, and you realise this engine offers up a far-from slouched approach to propulsion.

The 640i xDrive has a 3.0-litre six-cylinder turbocharged engine with 250kW of power and 450Nm of torque. It gets the same eight-speed auto, but as the xDrive naming indicates, it's all-wheel drive.

But this is the one you'd prefer if you want to hit highway speed in a hurry - the 0-100km/h claim is 5.3 seconds, where the 630i takes a full second longer (6.3sec) according to the company.

Well, BMW tells us you’ll return 10.7-10.8 litres per hundred kilometres on the combined cycle. But we would suggest that’s unlikely, unless you have Miss Daisy lounging in the back seat. Drive it like you definitely will drive it, and you can expect to pay for that privilege at the pump. 

Emissions are a claimed 243-246g/km of CO2, and the M5 Competition’s 68-litre tank will demand a premium unleaded petrol.

BMW claims fuel use of 7.0 litres per 100 kilometres, and you'll need to use 95RON premium unleaded when you fill up.

On my trip with the car, I saw about 9.0L/100km across mostly high-speed driving - some freeway, some highway, some country back road touring, and quite a bit of corners and city stuff thrown in as well. I think that's pretty respectable.

What wasn't so great was the lack of premium fuel in some of the 'away from civilisation' places on my route home. Keep that in mind if planning your own GT long-distance cruise.

Things this large simply shouldn’t be this potent. Like John Goodman suddenly toppling Usain Bolt at the Olympics, the BMW M5 Competition is bulk-defyingly good at the fast stuff.

The secret is its ability to hide those sprawling dimensions on a race circuit or twisting road. BMW’s engineers have poured plenty of work into stiffening the chassis of the M5 Competition, from new anti-roll mounts to additional under-bonnet bracing, to make the brand’s biggest performance sedan feel more lithe and responsive when pushed. 

And while its size never vanishes completely - and you find yourself praying you don’t encounter oncoming traffic on skinnier roads - engaging the Competition’s sportiest settings unlocks a Copperfield-level vanishing act.

The engine helps too, of course, pushing the M5 along with staggering ease, even when you’re pottering at suburban speeds. But really flatten your foot and the big V8 will force you to reassess your knowledge of physics. It’s really very fast, the Competition, the power flowing uninterrupted to the tyres, the engine still very willing to deliver more oomph long after your courage has jumped ship. 

The steering, direct though it is, lacks some natural feel, but you are always left with the impression that the Competition is going to go where you point it.

More fun stuff? Well, you can switch the traction control to a half-off setting, allowing for some smoking, drifting heroics before it drags you back into line. BMW calls it M mode, and it’s designed to make a hero of even the most ham-fisted of pilots, myself included. The braver still can deactivate traction control all together which, combined with rear-wheel-drive mode, turns the M5 Competition into the biggest and possibly most expensive drift car of all time .

Away from the track, though, the Competition version of the M5 is almost as good as transforming into a comfortable everyday commuter as its less hairy siblings. The adaptive suspension can be softened, and the steering lightened, to make toppling traffic a doddle. 

The keen-eyed among you might well have noticed we’re yet to touch on any major downsides of the drive experience. And you'd be correct. 

I'll put this out there - if you like to drive, there are BMW models for less than this one that will put a much bigger smile on your face. Like, a 440i Gran Coupe, or even just a 330i sedan…

But if you're in BMW's target market - that being older executive buyers who want space and luxury as a priority over thrills at the wheel, you could do a lot worse.

That's because the 6 Series GT lopes along the highway without fuss - the engine easily coping with the demands of overtaking moves, the adjustable drive modes allowing a light steering and wafting suspension feel to wile away the kilometres.

There are 'Comfort' and 'Comfort Plus' modes, but the latter is a bit too spongy and can be boaty feeling. The Comfort setting is made for the highway.

It is actually pretty agile for its dimensions.

If you decide to deviate from the straight sections, you'll be able to explore a little bit of dynamic range, especially when you dial up the 'Sport' mode, which changes the damper settings, steering weight, throttle and transmission response, and even the digital dials in front of the driver to a more aggressive look.

Our car had the 'Integral Active Steering' setting, which is a variable ratio steering system that includes rear steering - that essentially helps make is more turnable in corners at highway speed, and easier to park at lower speeds. It's difficult to say whether the assistance is excellent or not short of driving a car without the tech, but to this tester it was hard to hide the size and weight (1835kg kerb weight) of the vehicle.

That isn't to say it's clumsy or lumbering - it is actually pretty agile for its dimensions, though it makes a lot more sense on long drives and coastal cruises than it does in the narrow and twisty alpine roads of the Snowy Mountains Highway that I tested it on.

There's good grip from the tyres, and strong response from the powertrain - but if it were my money, and I had to have a 6 Series for whatever reason, I'd be looking towards the 640i model, which has a thumping six-cylinder with 250kW/450Nm - certainly an engine that would be more at home in this car. Plus that model comes with AWD.

The BMW 6 Series GT range has a five-star Euro NCAP crash test score based on 2017 testing, but it hasn't been scored by ANCAP.

There's the usual array of airbags - dual front, front side, full-length curtain and driver's knee airbags are included, plus parking sensors all around, and heaps of safety tech including the 'Driving Assistant Plus' package with lane departure warning and lane keeping assist, forward collision warning, auto emergency braking (AEB) front and rear, blind-spot monitoring and rear cross-traffic alert, and adaptive cruise control with stop and go.

That's all great stuff, and so is the 360-degree camera system with adaptive display - so, if you're reversing and you turn the wheel to one side, the image on screen will move, too. It'll also go between a birds-eye view and a backing-up perspective, and that can take some getting used to.

What was less convincing in terms of the user experience was the rear auto braking, which seemed to be scared of the car's own shadow. On multiple occasions the car jammed on the brakes when reversing out of driveways on to empty streets - be it in the normal height, or the raised height setting.

The 6 Series GT has dual ISOFIX anchor points and three top-tether points are there and ready for baby seats or child seats.

The ownership package is yet to be confirmed, the M5 Competition will be covered by BMW’s three-year/unlimited kilometre warranty. 

Service intervals are condition, rather than time or distance, based, so the car will tell you when servicing is required.

BMW runs a condition-based servicing plan, which means the car will tell you when it needs servicing. But you can rest assured it won't (theoretically) cost you much, with the brand's 'Service Inclusive' pack. It covers you for basic maintenance as and when required for five years/80,000km. According to BMW, that includes "annual vehicle checks, oil changes, all filters, spark plugs and labour costs for the duration of the package".

BMW offers a three-year/unlimited kilometre warranty plan, and you get the same cover for roadside assistance.