Audi A6 vs Mercedes-Benz AMG GT

What's the difference?

I was thoroughly impressed by the Audi A6 Allroad 45 TDI quattro 2020 model. It is excellent on road, resolved and comfortable on unsealed surfaces, and very well packaged for family touring.

I’d personally have it in a heartbeat over a Q7 or any SUV, for that matter. I can understand why some buyers wouldn’t consider it, but if you’re someone who likes to think outside of the boxy SUV, then be sure to take a look at the Audi A6 Allroad.

The GT63 4Matic+ is a breathtaking example of everything that Mercedes-Benz and AMG are.

Ferociously fast, incredibly agile and superbly sophisticated, it should be on anybody’s shortlist, if that also includes a Porsche, Aston Martin, Maserati or even a Lamborghini. And it’s definitely much more than yesterday’s SLC ever was – for similar money in today’s terms, as it turns out.

But, around Tasmania’s glorious roads at least, the Mercedes-AMG lacks the ride comfort and road noise isolation to be a fully-rounded-out GT, and that’s a disappointment for a brand with such formidable history in making such cars.

If this isn’t the best looking genre of car, I must have been blindfolded since birth. You might think differently - be sure to let me know in the comments section below.

But for me, I just love the idea of a station wagon that is beefed up with SUV styling cues, and the Audi Allroad formula has been en pointe for generations now. This latest A6 Allroad doesn’t disappoint, either, with all the elements you’d expect.

Things like the bulging contrasting wheel-arch liners, the rugged underbody protection bash plates, and even the silver roof rails and silver metallic side sill protectors with ‘quattro’ emblazoned upon them - it just all works. 

And being an Audi A6 wagon underneath the glittery bits, it’s a sizeable vehicle. The dimensions read like so: length - 4951mm; wheelbase - 2925mm; width - 1902mm; height - 1458mm, though that depends on the height of the air suspension. 

The A6 Allroad sits about 45 millimetres higher than the standard A6 Avant wagon (not sold in Australia). And the ground clearance also varies depending on the air suspension height setting, but it is officially recorded at 139mm - which isn’t very high at all, but that’s for the regular driving setup. In its raised height, that jumps by 45mm to 184mm. Nowhere near an off-road Toyota, but still high enough to stop the belly from scraping.

And there are other hardware bits to help you out if the going gets tough - out of sight is Audi’s ‘quattro’ all-wheel drive system with a self-locking centre differential that the brand says provides “superior traction and its high level of safety and agile handling”. There is hill descent control, and the infotainment screen can display the location, elevation, compass and driving angles, too.

As for the design of the interior? It’s high-tech Audi opulence and comfort at its best. Check out the interior pictures to see what I mean.

This is still clearly a Mercedes AMG GT coupe, like the 2014 C190 original, but a ground-up redesign sees it subtly yet significantly altered.

Some 270kg heavier than before, the larger-in-every-dimension body combines aluminium, steel, magnesium and fibre composite materials for improved rigidity and a lower centre of gravity. Length (4729mm) and wheelbase (2700mm) have been stretched by 177mm and 70mm respectively. Width (1984mm) and height (1352mm) are also up.

The nose treatment is similar to before, especially with the bulgy bonnet and signature vertical slatted grille fitted. These, combined with the LED digital headlight shape effect, is reminiscent of, but far-better executed than, the goofy-looking MG5’s face.

Underneath, it's an all-new platform shared with the SL, with the rear transaxle of the old car replaced by a permanent AWD system, leading from 46:54 front/rear weight distribution to 50:50 as a result.

That aggressive, exaggerated cab-backward/ultra-long bonnet silhouette that visually connected it with the SLS gives way to more-conventional and practical coupe proportions that is striking if not especially original, since they do look quite 911-esque. Along with the longer wheelbase and wider tracks, the result allows for two small rear seats to be fitted, while liftback cargo access remains.

Similarly, in the name of way-more usable interior packaging, Mercedes-AMG says it pushed the driving position nearly 180mm forward compared to the previous GT. Let’s see what that all looks like inside.

Technical. Practical. Glorious. Three words I’d use to describe the cabin of the Audi A6 Allroad. 

The cockpit isn’t anything out of the ordinary for an Audi of the modern era, and as such it will feel familiar to you if you’ve been in or around any of its more recent stablemates. It also means that you’ll find yourself in a high-end, high-tech and highly pleasant interior. The materials used are beautiful and of a high standard. They look very nice and it is an extremely pleasant place to be. And you can hate on me if you want, but I’m sold on brown leather. Yummo!

It will take some time for you to get to grips with the dual-touchscreen layout of the cabin, but once you get the hang of it, it becomes second nature.

The media screen is very easy to use, the menus are simple to learn, and over my week there were absolutely no issues with Apple CarPlay - either when connected via USB, or when used wirelessly.

The second screen below controls a lot of the main functions of the air conditioning system, and while I’m not a huge fan of using a screen to touch through temperature and fan controls, this one has haptic feedback and is well positioned - it’s not as much of a glance away from the road as in, say, a Land Rover or Range Rover. There’s also a volume knob which is good, and quick buttons for Drive Select and demister for front and rear windscreens.

In terms of the practicalities, there are bottle holders in the doors, a pair of cup holders between the front seats, a covered centre console bin with Qi wireless phone charging (remember not to leave your phone in there!) and there are two USB ports in there, plus a SIM card slot and SD card slot as well.   

The seat comfort is very good - there’s electric adjustment on both seats with lumbar adjustment, and the driver’s seat gets memory settings as well. The electric steering wheel adjust is a nice touch as well, and there’s a remote boot release trigger, too.

There are twin sunroofs, and the front one can tilt and slide while the rear one is fixed. It helps lighten things up a bit if you have the optional dark headlining, which I personally wouldn’t choose.

Rear seat space is excellent. Sitting behind my own 182cm driver’s seat position, I had easily enough legroom, headroom and shoulder room - in fact, the rear pew is so accommodating, it could easily fit three of me across - but foot space is a little tight due to the large transmission tunnel. 

Those in the back are well catered for – there are 2x USB ports, a pair of large door pockets with bottle holders, twin mesh map pockets, a flip down armrest with storage and cupholders, and our car had quad zone climate control (as part of the optional Premium Plus package - standard is three-zone climate), plus there are centrally mounted directional air vents and in the door pillars at face height. Our tester also had those optional manual sunblinds, which would certainly help those in the back get some shut-eye on longer trips. 

The centre section of the rear seat can be split folded down on its own as well – so you have 40:20:40 rear seat folding, which is great for skis or snowboards. Plus there are two ISOFIX child seat attachments and three top-tether points available for baby seats. And one of the most excellent additions to any car ever – illuminated seat belt buckle receivers. It just makes it that much easier to see at night.

If you need to fold down those rear seats, there are boot-mounted triggers. That’ll help expand the luggage capacity from the standard 565 litres (VDA) to an expansive 1680L (VDA). The cargo hold easily fit the three CarsGuide suitcases (124L, 95L and 36L) with room to spare.

There is no Audi Allroad seven seater, though. And that’s potentially where something like a Q7 makes more sense, depending on your intent. 

The first impression inside is that of space, despite the falling roofline and coupe-like upsweep of the side windows and you look back. While, again, similar to a 911s, a kink at the door gives the GT a unique character.

Even larger people will appreciate the generous amounts of room up front, with space to stretch, sat in sumptuously comfy bucket seats. Note that the standard ones are better than the racier but firmer Sports versions.

The driving position is perfect, ahead of a dashboard that is very typical modern Mercedes in appearance and layout.

To that end, the tablet-style integrated touchscreen (11.9 inches) is clear, fast and intuitive once time is taken to learn it. And points are also won for the multi-configurable electronic instrumentation, that allows for a variety of screens, including track, classic and minimalist views.

The trademark turbine air vents, the quite beautiful material and trim finishes and just the general solid feel are further typical contemporary Mercedes cabin treatments, as are the excellent ventilation and ample storage options.

And while rear vision isn't great, that's what cameras are for. It's all pretty much on brand.

It is a shame, given how elevated the Mercedes-AMG engineering is underneath, that the GT’s interior look and ambience is so similar to those of a (albeit higher-spec) C-Class or GLE. It's simply not as special as some of the company’s previous sports cars.

More annoyingly, the ride is too firm and bumpy for a GT, and this has the unhappy effect of provoking random rattly trim sounds within the cabin. It’s a bit like scrunched-up cellophane. In a $420K (as tested) Merc, that’s very disappointing, especially as it can be heard over the copious amount of road and tyre noise droning through, particularly on coarser bitumen surfaces.

Further back, the rear seat is strictly two-plus-two, and nobody over 150cm tall is recommended to travel there by Mercedes itself. That sloping roofline is the culprit. That said, brief trips with a bowed head are possible, as the fixed cushions and split-folding backrests are actually surprisingly comfy. But only for short journeys. Kids should love it though, and the second row does open up the GT’s usefulness enormously.

As does a near-doubling of the AMG’s cargo capacity, jumping 146 litres to 321L with backrests erect, to a whopping 675L (+325L) in two-seater mode. The flat floor is accessed via a large electrically-operated liftback door, offering quite a large aperture for easy loading/unloading.

Having no spare wheel helps here, with a tyre inflation kit included in lieu of that.

Meanwhile, at the front, under the bonnet, things have definitely changed for the better as well.

Starting from $370,400 (all prices are before on-road costs), the Mercedes-AMG GT63 4Matic+ is priced and positioned as something of an eagle amongst some pretty delectable doves, given its combination of four seats, 430kW of power, 800Nm of torque and four-wheel drive.

No rival equivalents can match the Mercedes on paper. The 398kW/610Nm 911 Carrera 4 GTS T-Hybrid offers less power but starts from $400,000-plus. The 410kW/650Nm GranTurismo Trofeo begins at $450K, the 500kW/800Nm DB12 from $455K and the 404kW/470Nm Continental GT from $460K.

Only the 460kW/750Nm BMW M8 Competition comes closest to the Mercedes-AMG, from $380K.

Side note, today’s GT is only slightly more expensive than what the 450SLC was nearly half a century ago when adjusted for inflation.

And, just like with that classic old Benz, it shares much with the brand’s legendary SL convertible stablemate – including, in this case, standard all-wheel drive and active rear-axle steering… aka 4WS to select third and fourth-generation Honda Prelude owners out there.

What else does $400K-plus buy you? As you’d expect, the GT63 4Matic+ comes choc-full of standard equipment, much of it typical of the luxury coupe breed, with leather-covered and electrically operated everything.

How about a front-axle lift system with GPS-enabled memory that automatically raises the GT’s nose to help clear bumps and then remembers to do so next time?

There are climate-controlled AMG sports seats with inflatable bolstering and massaging functionality, a fixed glass roof, a head-up display, augmented-reality satellite navigation, 360-degree surround views, performance telemetry data as part of an extensive multimedia system, an 11.9-inch portrait touchscreen, 11-speaker Burmester audio, a handsfree-powered tailgate, 21-inch alloys and cutting-edge driver-assist safety tech. More on that in the Safety section below.

Then there are the myriad option packs, bumping the GT63’s price up towards $500,000. These include a $2.7K seat trim package; a $10K AMG Night Package that adds darker trim treatments (often where chrome was); an aerodynamics package with fixed spoiler replacing the standard active spoiler; a $2.6K AMG Performance Seat package; a $13K Carbon Fibre package and $13.2K Ceramic Brakes.

Now, while the new GT does ditch the previous model’s unique rear transaxle spaceframe pioneered by the gull-winged SLS of the early 2010s, the resulting longer wheelbase and shorter overhangs do provide less outlandish and more practical design.

Let’s check that out in more detail. 

Under the bonnet of the Audi A6 Allroad is what Audi labels the ‘45 TDI’ - a 3.0-litre turbo-diesel V6 engine that produces 183kW of power (from 2750-4500rpm) and 600Nm of torque (from 1500-3000rpm).

The engine is only available mated to an eight-speed torque-converter automatic transmission and Audi’s renowned ‘quattro’ all-wheel-drive (AWD) system. 

Audi claims this 1980kg wagon can run from 0-100km/h in just 6.5 seconds, on its way to a top speed of 250km/h. It is a hummer of an engine - more on that in the driving section below.

Towing capacity is pegged at 750kg for an unbraked trailer, and maxes out at 2500kg for a braked trailer.

Should Aussies feel short changed when it comes to the engine options here? Arguably, yes - and that’s despite the powertrain offered here still being a stormer. 

There’s only one spec available Down Under, and even it doesn’t get the most up-to-date emissions tech. There isn’t AdBlue urea treatment (meaning this is a Euro 5 engine), and our cars have essentially been de-specced to miss out on the latest 48-volt mild-hybrid tech, which is standard on all grades of the A6 Allroad in Europe. Maybe that is part of the reason the cost is down, this time around. 

And while the outputs of the 45 TDI in Australia are pretty decent, other markets have the A6 Allroad offered in 50 TDI (210kW/620Nm) and 55 TDI (257kW/700Nm) trims. Remember, though - this is a very niche player here. 

There’s a plaque signifying which engineer “handcrafted” the GT’s engine – in this case, the famous M177 in 3982cc, 4.0-litre twin-turbo intercooled V8 petrol guise.

Delivering 430kW of power at 6500rpm and 800Nm of torque from 2500-4500rpm, it sends drive to all four wheels via a nine-speed multi-clutch transmission (dubbed MCT in AMG-speak), catapulting the GT63 4Matic+ from 0-100km/h in just 3.2 seconds, on the way to a top speed of 315km/h.

How does it do that?

With AWD, the GT is now nearly 15 per cent heavier than before, but it still manages a punchy 218kW/tonne. Active aerodynamics over, inside and under a more-rigid body structure also helps.

The AMG 4Matic+ AWD system goes from 50/50 front/rear, to 100 per cent rear, variable torque distribution according to conditions and settings, and backed up by an electronic limited-slip differential. Among the many driving settings are Race Start, Drift Mode and good-old Comfort, if it all becomes too much.

Also keeping all that performance in check is a high-performance composite brake setup with improved cooling for faster responses.

Interlinked active roll bars improve body control, the five-link independent suspension features adaptive dampers for a softer ride.

And, as for that 4WS tech, the rear wheels steer opposite to the fronts at up to 100km/h (by some 2.5 degrees) for tighter and tidier handling, or 0.7 degrees in the same direction above 100, for greater stability and road-holding.

Its effect on the way this near-two-tonne coupe zigs and zags around corners is something you need to experience to really appreciate.

Audi claims the 45 TDI powertrain in the A6 Allroad will use 6.6 litres per 100 kilometres. That’s the official Australia fuel consumption figure on the combined-cycle test. CO2 emissions are claimed at 174g/km.

During my time in the Audi A6 Allroad I saw an average fuel use return of 7.4L/100km - which was taken over highways, back roads, unsealed roads and twisty bits. There was even some urban stop-start in there, too. I think that’s pretty darn good for a car of this size.

Fuel tank capacity is 63 litres, meaning a real-world range of 851km based on my fuel consumption.

As mentioned above, the A6 Allroad is a mild hybrid model in other markets, but not in Australia. We don’t even get the Euro 6-compliant version here, as there’s no incentive for it to be offered locally - as in, there’s not even AdBlue treatment. 

There’s no electric version (though you might want to look at the all-new Audi e-tron)  or plug in hybrid, and no petrol model either.

Actually, the GT’s economy isn’t horrendous considering how fast it can go.

Even blasting a few times around beckoning country roads, we managed an indicated 13.0L/100km, which is an improvement on what Mercedes-AMG says the GT averages the 14.6L/100km average that Mercedes-AMG officially states.

That translates to a carbon dioxide emissions rating of 334g/km.

Using 98 RON premium unleaded petrol, an average of just under 480km between refills of the 70L tank is possible. The urban run sees consumption rocket to 21.8L/100km (for just 321km of range), or 10.4 out on the highway run, meaning that over 670km is possible should you decide to drive in a docile manner.

Here’s where the A6 Allroad separates itself from, say, an Audi Q5 or Q7. It’s a low-slung wagon, made for touring on country roads, doubling down on dirt backtracks and cruising comfortably on the freeway.

It’s not as upright as a Q5 or Q7, and that means it has a lower centre of gravity - so it feels more hunkered down, more settled into the surface below.  

And in the case of the A6 Allroad, there’s adaptive air suspension all around to cushion the car from what lies beneath. For the most part, that air suspension is superb - it absorbs big bumps and lumps very well, though the oversized 21-inch optional wheels can’t disguise sharp edges from those in the cabin. 

The general compliance is very good, and as I found out first hand, you can easily soak up hundreds of kilometres without feeling the affects of the road underneath you - even over bumpy country back roads and lumpy dirt sections.

The steering could be better; it’s a little bit vague and heavy on centre at higher pace, but at lower speeds it is light and amicable. Very easy to park despite its size, and easy to manoeuvre around town, too.

The engine builds pace with superb linearity, and it’s very quiet and refined as well. There is a tiny bit of turbo lag at lower speeds or from a standstill – but it is completely manageable and never feels like it’s sluggish at all. The 0-100km/h claim of 6.5 seconds seems achievable, too. 

The eight-speed automatic transmission was mostly very smart and well sorted - although in other VAG models with this engine family/eight-speed auto, the transmission never felt quite as busy at higher speeds. I noticed it shuffling between seventh and eighth gears more than I was expecting, given how much torque the engine has. It’s not annoying at all, and nor is it unrefined, and could well have something to do with attempting to save fuel rather than leaving it in top gear.

During night driving, the optional HD Matrix LED headlights were exceptional - among the best headlight technology that I’ve ever encountered. The ‘matrix’ technology means they can blank out oncoming traffic or cars in front of you while keeping the high-beam on in other areas. The auto headlights with auto high beam worked very well, too.

The plan was never to do a serious off road review, but I did do some driving on unsealed roads and found the Allroad to be excellent. 

Through slippery unsealed corners it exhibited excellent traction, though you can feel the weight of the car shifting from side to side when you pivot through corners. There was a touch of skittishness over mid-corner bumps, but again that could be more to do with the big wheels than anything else.

I came away thinking that if you had your eyes closed, you wouldn’t even know that you were on dirt or gravel. It really is an exceptional car across sealed and unsealed roads. 

Nobody will drive the GT63 4Matic+ and think, ‘Oh, this is OK’, because its breadth of performance is phenomenal.

No matter which mode you're in, from Comfort through to track-tuned Race, the Mercedes-AMG blends forceful pace and commanding control without ever breaking a sweat.

Flex your right foot and the two-tonne coupe bounds into action like a giant on a mission, striding past posted speed limit signs in nanoseconds and way, way faster than the law will stand if diligence isn’t exercised.

And there’s no point relying on seat-of-your-pants sensations, either, because the chassis below embraces the road with an almost zealous devotion. Which is astounding, given how agile the four-wheel steering-enhanced handling is.

The 63’s super power is exactly that – it dulls your sense of speed. One tester admitted to exceeding 150km/h before noticing. An odd confession considering the sonic boombox that is the bi-turbo V8’s howl.

But jailbait performance is not even the 63’s most lingering joy. That would be its steering perfection, that delivers that rare trifecta of keenness, crispness and communication. The wheel feels eager and alive in your hands, even when powering between tight turns, backed up by sensational grip and control. How can a two-tonne GT handle so sharply?

Warm, dry roads were the order of the day, so we can’t tell you how the 4Matic+ permanent AWD system deals with wet or slippery surfaces, but the slick multi-clutch transmission, seamless torque-vectoring tech and sticky tyres more than cope with the 63’s formidable outputs.

So, that's the gushing part out the way, then.

Despite the adaptive dampers, rigid architecture and exquisitely sophisticated suspension, the ride is simply too stiff in Comfort mode, and downright jittery on some of the Tasmanian roads we tested on, for the 63 to be considered a true luxury grand tourer. It just isn't comfortable, luxurious or supple enough.

Plus, grippy as they are, the 21-inch wheels transmit too much road and tyre noise through to the cabin, meaning that the GT isn't as quiet as you'd hope. Add the aforementioned trim squeaks, and the expected cocooned silence isn’t always there.

The upshot is that the 63 possesses more of a sports car character than a luxury GT character. Great news if you're a 911 type buyer and are seeking a high-performance 2+2 alternative, but a disappointment if comfort and refinement are priorities.

Still, it is impossible not to be deeply moved by this Mercedes-AMG.

While the GT doesn’t score an ANCAP rating – probably because it’s too expensive to crash test – we’d wager that it would be above-average, given Benz’s track record as a pioneer in this field.

That’d due to the scores of active, passive and driver-assist safety features fitted, from multi-faceted autonomous emergency braking (AEB) and lane-support systems to Mercedes’ PRE-SAFE tech that anticipates a crash and then prepares the car for impact.

More specifically, the GT includes Active Lane Change/Keep Assist, adaptive high beam as part of its megapixel LED set-up, adaptive cruise control, Cross-Traffic Assist, Evasive manoeuvre support, an emergency services call-out system, 360-degree camera views, pedestrian protection bonnet and eight airbags.

In other Mercedes products of today, AEB operating parameters are 7-80km/h for vulnerable road users like pedestrians and cyclists, and from 7-250km/h for vehicle-to-vehicle, while the lane-keep support systems operate between 60-200km/h.

Finally, there are ISOFIX child-seat anchorages in the front passenger seat and two in the rear seats.

Audi offers a three-year/unlimited kilometre warranty, which is as good as BMW, but not as good as Lexus (four years/100,000km) or Mercedes-Benz, Volvo and Genesis (five years/unlimited kilometres). It’s falling behind in the luxury sphere.

The company offers reasonably priced capped price ownership plans for maintenance. Purchasers can roll in the cost of either a three-year service plan ($2170) or a five-year plan ($3300). That covers off the usual service items due every 12 months/15,000km.

Roadside assist is included for the period of the new car warranty.

What’s the GT like to own?

Mercedes-Benz offers a five-year/unlimited km warranty, with five years of roadside assistance. This is average for most mainstream and luxury brands, but superior to most sports-car makers like Porsche and Lamborghini.

Intervals are every 12 months or 20,000km, and while no capped-priced servicing is offered on the GT, pre-paid three-, four- or five-year service plans are available, ranging from $5165, $7700 and $8665 respectively.

Big performance demands big maintenance bills, it seems.