BMW 6 Series vs Mercedes-Benz E53

What's the difference?

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.

As it turns out, the automotive world really doesn’t need an E63 S Coupe, because the E53 Coupe really does give you all you’ll ever need.

Simply put, the E53 Coupe’s balance of performance and luxury is bang on, while an E63 S Coupe would arguably prioritise one too much over the other.

Indeed, if you’re interested in a ‘relatively affordable’ grand-tourer that can get up and go when required, you could do a lot worse than the E53 Coupe.

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.

The E53 Coupe already had an alluring exterior design, but in facelifted form, it looks even better.

The big changes are up front, where the E53 Coupe now has Mercedes-AMG’s signature Panamericana grille insert, with the multi-louvre aesthetic previously the reserve of its ‘63’ models.

In fact, the entire fascia has been redesigned, with the grille flipped upside down, while the Multibeam LED headlights are flatter and therefore angrier. Naturally, the bonnet and bumper have been tweaked to match, with the former featuring strong powerdomes.

Around the swoopy sides, a sporty set of black 20-inch alloy wheels is new, matching the window trim, while the only differences at the rear are the fresh graphics of the LED tail-lights.

Yep, the E53 Coupe still has a subtle bootlid spoiler and a prominent diffuser insert, which integrates the quad round tailpipes of its sports exhaust system.

Inside, the midlife facelift really makes itself known with its new flat-bottomed steering wheel with capacitive buttons and haptic feedback. This set-up is… fiddly, with presses often confused for swipes, so it's not exactly a step in the right direction.

And that’s particularly annoying because these controls are used for the carryover 12.3-inch touchscreen and 12.3-inch digital instrument cluster, which are now powered by Mercedes’ MBUX multimedia system, which bundles in Apple CarPlay and Android Auto support.

While now familiar, this set-up remains the benchmark in nearly all regards and is therefore a brilliant upgrade for the E53 Coupe, thanks to its speed and breadth of functionality and input methods, including always-on voice control and a touchpad.

Materials-wise, Nappa leather upholstery covers the seats and steering wheel as well as the armrests and door inserts, while Artico leatherette trims the upper dashboard and door shoulders.

Conversely, hard, shiny plastics adorn the lower door panels. Given that ‘cow hide’ and other soft-touch materials are used on most other surfaces, it’s unusual that Mercedes-AMG didn’t go the whole way.

Elsewhere, open-pore wood trim features prominently, while metallic accents brighten things up alongside the sporty stainless-steel pedals and smile-inducing ambient lighting.

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.

Measuring 4835mm long (with a 2873mm wheelbase), 1860mm wide and 1430mm tall, the E53 Coupe is a genuinely large car, which is great news for practicality.

The boot has a pleasing cargo capacity of 425L, but it can be increased to an undisclosed volume by stowing the 40/20/40 split-fold rear bench via the handy manual release latches.

It’s worth noting that while the aperture is wide, it’s not tall, which could be a problem for bulkier items alongside the tall load lip, although two tie-down points are on hand for securing loose items.

However, what really impresses is the amount of space inside. While the front sports seats are comfortable, the two rear passengers are in for the bigger treat, with room plentiful, mercifully ending the argument of who gets stuck in the uncomfortable second row.

Behind our 184cm driving position, there’s two inches of legroom as well as an inch of headroom, although toe-room is almost non-existent.

Being a four-seater, the E53 Coupe divides its rear occupants with a tray that contains two cupholders, while they also have access to two side cubbies and a small central cubby with two USB-C ports. This cubby is positioned between the air vents at the rear of the centre console.

And yes, even child seats can be fitted, with two ISOFIX and two top-tether anchorage points available should they be required. In fact, the long front doors make this task less challenging, although those big doors do become problematic in tight carparks.

All of that’s not to say occupants in the first row aren’t treated well, because they are, with the centre console’s cubby featuring two cupholders, a wireless smartphone charger, a USB-C port and a 12V power outlet.

Other storage options include the decently sized central bin, which contains another two USB-C ports, while the glovebox is also of a decent size, and then there’s the overhead sunglasses holder.

Priced from $164,800 plus on-road costs, the facelifted E53 Coupe is actually a staggering $14,465 more affordable than its predecessor.

But if you’re not a fan of its body-style, the $162,300 E53 sedan (-$11,135) and $173,400 E53 Cabriolet (-$14,835) are also available.

Either way, standard equipment not already mentioned includes metallic paintwork, dusk-sensing lights, rain-sensing wipers, power-folding side mirrors with heating, keyless entry, rear privacy glass and a power-operated bootlid.

Inside, push-button start, a panoramic sunroof, satellite navigation with live traffic, digital radio, a 590W Burmester surround-sound system with 13 speakers, an augmented reality (AR) head-up display, a power-adjustable steering column, power-adjustable front seats with heating, dual-zone climate control and an auto-dimming rearview-mirror feature.

Direct rivals for the E53 Coupe are non-existent, with the closest being the smaller – and therefore much more affordable – BMW M440i Coupe ($118,900) and Audi S5 Coupe ($106,500). Yep, it’s a unique offering on the market, this Merc.

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.

The E53 Coupe is powered by a 3.0-litre inline six-cylinder petrol engine that produces a hearty 320kW of power at 6100rpm and 520Nm of torque from 1800-5800rpm.

The unit in question has one traditional turbocharger and an electric-powered compressor (EPC), which is available at engine speeds up to 3000rpm and can spool up to 70,000rpm in just 0.3 seconds for instantaneous punch.

But that’s not all, because the E53 Coupe also has a 48V mild-hybrid system called EQ Boost. As its name suggests, it has an integrated starter-generator (ISG) that can provide up to 16kW and 250Nm of temporary electric boost.

Mated to a nine-speed torque-converter automatic transmission with redesigned paddle-shifters, and Mercedes-AMG’s fully variable 4Matic+ all-wheel-drive system, the E53 Coupe sprints from a standstill to 100km/h in a handy 4.4 seconds.

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.

The E53 Coupe’s fuel consumption on the combined-cycle test (ADR 81/02) is 9.3L/100km, while its carbon dioxide (CO2) emissions are 211g/km.

Given the performance on offer, both claims are pretty good. And they’re made possible by the E53 Coupe’s 48V EQ Boost mild-hybrid system, which has coasting and extended idle-stop functionality.

That said, in our real-world testing, we averaged a more realistic 12.2L/100km over 146km of driving, although the launch test route only involved high-speed country roads, so expect a higher result in metropolitan areas.

For reference, the E53 Coupe has a 66L fuel tank, and it will only drink more expensive 98RON premium petrol.

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.

If an E53 Coupe was your daily driver, you’d be very happy, because its balance of comfort and performance is just about as good as it gets.

Stick the boot in and the engine responds with a level of enthusiasm that only electrification can provide. Not only does the ISG provide timely thrust, but the EPC helps the E53 Coupe reach its maximum torque, although it has to work harder for peak power.

That said, despite the addition of the EQ Boost system and the EPC, the E53 Coupe still feels like a proper Mercedes-AMG model, staying true to the high-performance mantra while offering a different approach.

Critically, all the drama is there, as it charges towards the horizon with intent as the transmission swaps gears smoothly, providing relatively quick shifts and revving on the down changes when required. It all adds up to a properly exciting drive.

However, it’s the E53 Coupe’s sports exhaust system that’s likely to command all the attention with its crackles, pops and overall booming soundtrack in the Sport mode. It can also be manually engaged in any mode by pressing a button in the centre console.

And given the E53 Coupe’s 4Matic+ system is fully variable, it offers plenty of grip when briskly accelerating and enjoying the soundtrack, but its rear end can still step out briefly when cornering hard.

Speaking of handling, the E53 Coupe goes around corners surprisingly well, defying its large dimensions and considerable 2021kg kerb weight by exhibiting strong body control.

Coming into bends, the E53 Coupe can also lean on its sports brakes, which pull up with absolute confidence.

And when you’re guiding the E53 Coupe through the twisty stuff, the electric power steering comes to the fore, with its speed-sensitivity and variable ratio.

The steering set-up is somewhat disappointing at times, however, with the feedback not quite up to the level of a proper performance car.

That said, it is quite direct and feels meaty in hand – two traits that are necessary for success – with this heft increased in the Sport drive mode. Comfort is where it’s at, though, if you ask me.

That said, the E53 Coupe’s suspension uses air springs and adaptive dampers to make it a comfortable cruiser.

Sure, this set-up’s tune does prove to be a little firm on lower-quality country roads, with most bumps and lumps felt by occupants, but on well-maintained highways and city roads, it’s got suitable levels of smoothness.

In keeping with this luxurious feel, the E53 Coupe’s Noise, Vibration and Harshness (NVH) levels are pretty damn good, with tyre roar and wind whistle easily missed while enjoying its aforementioned Burmester sound system.

ANCAP awarded the fifth-generation E-Class sedan and Estate its maximum five-star rating in 2016, although it doesn’t apply to the E53 Coupe, due to its differing body-style.

That said, advanced driver-assist systems still extend to autonomous emergency braking with pedestrian detection, lane-keep and steering assist (including emergency), adaptive cruise control with stop and go functionality, traffic-sign recognition, driver-attention alert, high-beam assist, active blind-spot monitoring and cross-traffic alert, tyre-pressure monitoring, park assist, surround-view cameras and front and rear parking sensors.

Other standard safety equipment includes nine airbags, anti-skid brakes and the usual electronic traction and stability-control systems.

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.

Like all Mercedes-AMG models, the E53 Coupe comes with a five-year/unlimited-kilometre warranty, which is currently the benchmark in the premium market. It also comes with five years of roadside assistance.

Better yet, the E53 Coupe’s service intervals are rather long, at every year or 25,000km – whichever comes first.

It’s also available with a five-year/125,000km capped-price-servicing plan, but it costs an expensive $5100 in total, or an average of $1020 per visit, with the E53 Coupe’s fifth trip charging $1700 alone. Ouch.