Audi S8 vs Mercedes-AMG GLE63

What's the difference?

The S8's existence is a source of joy for me because it's not a huge SUV. Yes, it's a huge sedan but it's a reminder that the technological flagship is alive and well, at least in Germany. And the important thing about these cars is the way the toys filter down through the rest of the range. That used to take years but we're seeing this cool stuff a lot more quickly, right down to the A1.

The S8 punches, and punches hard in this rarefied part of an already shrunken section of the market - the twin-turbo V8 matches its German rivals, it's lighter and it's as well-stacked as any of the three. What it doesn't do, however, is shout about itself the way the other two do.  It's the incognito choice.

There’s little wonder the GLE63 S is back for a second go around, after  clearly putting the frighteners on the Audi RS Q8 and BMW’s X5 M Competition and X6 M Competition.

After all, it’s a large SUV that sacrifices little in the way of practicality (especially the wagon) in its pursuit of high performance.

And for that reason, we’re itching to go for another drive – with or without the family.

Note: CarsGuide attended this event as a guest of the manufacturer, with travel and meals provided.

The sheetmetal is obviously very restrained given it's an Audi first, and secondly, it's just not done to go wild in this part of the market.

It's an A6 that's joined a gym, but didn't join that weird gym with men that can't run after you when you insult them (don't ask how I know this). Rolling on 21-inch wheels as standard, you can go up to massive 22s if you so choose.

The A8 created a subtle redirection of Audi's passenger car look, with the updated A4 and A6 both picking up on the horizontal bar between the rear lights and the huge grille framed by family lights with signature DRL patterns. The S8 builds on that with subtle S cues but nothing even vaguely shouty.

The interior acreage - or 'cabin', if you will - is very comfortable, but you already knew that. The multi-screen layout was first seen in the A8 and has now found its way into A7, Q8 and Q7 and is, as ever, brilliant to look at and use.

The MMI updates that have found their way into other cars are present and correct. Like the exterior, it's very restrained but not to the point of sparse minimalism, despite the lack of switches and buttons.

I really don't like the steering wheel, though, and I can't put my finger on why. It certainly isn't especially sporty-looking but I wonder if the standard flat-bottomed S wheel just looked stupid.

The materials are beautiful and everything fits together perfectly.

First things first, the new GLE63 S is available in two body-styles, with the wagon appealing to the traditionalists out there, while the coupe targets the style-conscious.

Either way, few large SUVs are as imposing as the GLE63 S, which is a good thing considering it wants to be taken seriously.

Up front, it’s immediately identifiable as a Mercedes-AMG model thanks to its distinctive Panamericana grille insert.

The angry look is punctuated by the angular daytime running lights integrated into the Multibeam LED headlights, while the chunky front bumper has large air intakes.

Around the side, the GLE63 S stands out with its aggressive wheelarch extensions and side skirts, with the wagon getting 21-inch alloy wheels as standard, while the coupe gets 22-inch items.

From the A-pillars onwards, the differences between the wagon and coupe body-styles start to become apparent, with the latter’s roofline much more steeply raked.

At the rear, the wagon and coupe differentiate themselves even more clearly with their unique tailgates, LED tail-lights and diffusers. That said, they do have a sports exhaust system with squared-off quad tailpipes in common.

It’s worth mentioning that the difference in body-style also means a difference in dimensions, with the coupe 7mm longer (4961mm) than the wagon, despite having a 60mm-shorter wheelbase (2935mm). It’s also 1mm narrower (2014mm) and 66mm shorter (1716mm).

Inside, the GLE63 S separates itself with its flat-bottom steering wheel with Dinamica microfibre accents, and multi-contour front seats, which are upholstered in Nappa leather alongside the armrests, dashboard and door shoulders and inserts.

The door bins are of the hard plastic variety. That’s underwhelming in a vehicle that costs this much, as you would hope cow hide – or at least a soft-touch material – would be applied to them.

The black headliner acts as another reminder of its performance focus, and while it makes for a darker cabin, metallic accents feature throughout, while the trim (our test vehicle had open-pore wood) adds some variety alongside the ambient lighting.

That said, the GLE63 S is still filled to the brim with cutting-edge technology, including two 12.3-inch displays, with one the central touchscreen and the other a digital instrument cluster.

Both use Mercedes’ MBUX multimedia system and feature Apple CarPlay and Android Auto support. This set-up is still the benchmark, thanks to its speed and breadth of functionality and input methods, including always-on voice control and a touchpad.

The cabin is clearly built with rear seat passengers in mind, with rear leg and headroom configured for those continent-crossing drives.

The S8 has plenty of comfort for two rear seat passengers and a few amusing options to while away the hours in traffic or on the autobahn.

That doesn't mean the front seat passengers are in purgatory, with huge but supportive seats adjustable in all conceivable directions.

Front and rear rows score a pair of cupholders and bottle holders while the boot is a handy, if not awe-inspiring, 505 litres.

Being a large SUV, you’d expect the GLE63 S to be quite practical, and it is, but what you wouldn’t expect is the coupe to have 25L more cargo capacity than the wagon, at a generous 655L, due to its higher window line.

That said, when you stow the 40/20/40 split-fold rear bench via the second row’s release latches, the wagon has a significant 220L advantage over the coupe, at a cavernous 2010L, thanks to its boxier design.

Either way, there’s a small load lip to contend with, making loading bulkier items a little more difficult, although that task can be made easier with the flick of a switch, as the air springs are able to lower the load height by a handy 50mm.

Better yet, four tie-down points are on hand to help secure loose items,  alongside a couple of bag hooks, while a space-saver spare resides under the flat floor.

In the second row, things are even better, with the wagon offering a crazy amount of legroom behind our 184cm driving position, as well as two inches of headroom for me.

With its 60mm-shorter wheelbase, the coupe naturally sacrifices some legroom, but it still provides three inches of legroom, while its sloping roofline trims headroom to an inch.

No matter the body-style, the five-seat GLE63 S is wide enough to seat three adults abreast with few complaints, with the transmission tunnel on the smaller side, meaning there’s plenty of room for feet.

There’s also plenty of room for child seats, with two ISOFIX and three top-tether anchorage points on hand for fitting them.

Amenities-wise, rear occupants are treated to map pockets on the front-seat backrests, as well as a fold-down armrest with two cupholders, while the door bins can accommodate a couple of regular bottles each.

A  fold-out cubby is positioned below the air vents at the rear of the centre console, containing two slots for smartphones as well as a pair of USB-C ports.

In the first row, occupants have access to the centre console’s cubby, which features two temperature-controlled cupholders, in front of which are a wireless smartphone charger, two USB-C ports and a 12V power outlet.

The central storage bin is pleasingly large and contains another USB-C port, while the glovebox is also on the larger side, and you get an overhead sunglasses holder too. Stunningly, the front door bins can take three regular bottles apiece. Not bad.

While the wagon has a large, square rear window, the coupe’s is a letterbox in comparison, so rearward visibility isn’t one of its strong suits.

Priced from $220,600 plus on-road costs, the new GLE63 S wagon is $24,571 dearer than its predecessor. While the rise is unfortunate, it is accompanied by the fitment of a lot more standard equipment.

And the same is true of the new GLE63 S coupe, which is priced from $225,500, making it $22,030 more expensive than its forebear.

Standard equipment for both cars includes metallic paintwork, dusk-sensing lights, rain-sensing wipers, power-folding side mirrors with heating, side steps, soft-close doors, roof rails (wagon only), keyless entry, rear privacy glass and a power-operated tailgate.

Inside you score push-button start, a panoramic sunroof, satellite navigation with live traffic, digital radio, a 590W Burmester surround-sound system with 13 speakers, a head-up display, a power-adjustable steering column, power-adjustable front seats with heating, cooling and massaging functionality, heated front armrests and outboard rear seats, four-zone climate control, stainless-steel pedals and an auto-dimming rearview-mirror feature.

Rivals for the GLE63 S include the less expensive Audi RS Q8 ($208,500) and BMW’s X5 M Competition ($212,900) and X6 M Competition ($218,900).

Under that long bonnet is a 4.0-litre twin-turbo V8 pumping out 420kW and a diesel-like 800Nm of torque. 

That's a lot, even for this big bruiser. Obviously, being an Audi S-car, it has quattro all-wheel drive, which is fed by an eight-speed ZF automatic. Which is in everything now. Well, just about.

That huge torque figure is available between 2000rpm and 4500rpm while peak power arrives at 6000rpm. The 0-100km/h sprint is despatched in - gulp - 3.8 seconds.

As it's riding on the MLB platform, the mild hybrid system is a 48-volt set-up. A lithium-ion battery in the boot takes charge from the belt alternator/starter, which means the S8 can coast at higher speeds with the engine off and also cut out at 22km/h and under in traffic.

The system can also add up to 60Nm of torque in the right conditions for up to six seconds, and if it happened for me, I didn't notice it.

The GLE63 S is powered by Mercedes-AMG’s ubiquitous 4.0-litre twin-turbo V8 petrol engine, with this version pumping out a hard-hitting 450kW of power at 5750rpm and 850Nm of torque from 2250-5000rpm.

But that’s not all, because the GLE63 S 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 electric boost in short bursts, which means it can also reduce the sensation of turbo lag.

Mated to a nine-speed torque-converter automatic transmission with paddle-shifters, and Mercedes-AMG’s fully variable 4Matic+ all-wheel-drive system, the GLE63 S sprints from a standstill to 100km/h in just 3.8 seconds, in either body-style.

The 10.5L/100km official figure is, shall we say, optimistic. The launch drive was mostly highway so there's no real information to be gleaned from that, so we'll have to wait for real world fuel figures.

I'd say 12-13L/100km is achievable if you don't like having fun, in which case, the lesser A8 is probably for you.

Audi says the MHEV system saves 0.8L/100km with an early cut-out for the stop-start and the ability to coast on the highway for over half a minute at a time.

The GLE63 S’s fuel consumption on the combined-cycle test (ADR 81/02) varies, with the wagon achieving 12.4L/100km, while the coupe needs 0.2L more. Carbon dioxide (CO2) emissions are 282g/km and 286g/km respectively.

When you consider the high level of performance on offer, all of these claims are fairly reasonable. And they’re made possible by the engine’s cylinder-deactivation technology and the 48V EQ Boost mild-hybrid system, which has coasting and extended idle-stop functionality.

That said, in our real-world testing with the wagon, we averaged 12.7L/100km over 149km. While that’s a surprisingly good result, its launch drive route mainly consisted of high-speed roads, so expect a much higher number in metropolitan areas.

And in the coupe, we averaged a higher but still respectable 14.4L/100km over 68km, although its launch  route purely involved high-speed country roads, and you know what that means.

For reference, the wagon has an 80L fuel tank, while the coupe has an 85L unit. Either way, the GLE63 S only takes more expensive 98RON premium petrol.

Driving any of the cars in this segment is a rare treat, whether it's the 'entry level' diesel or this top of the heap sports sedan. My day with the S8 was filled with the usual surprise and delight that only these tech-packed cars can deliver.

Heading out of the Sydney CBD in 'Comfort' mode, the car scans the road ahead and adjusts the active suspension accordingly. You already know it has active suspension because when you pull the door handle, the car lifts by 50mm to make it a bit easier to get in.

The suspension's party trick is flat-topped speed bumps - drive at one, brake a little and sense the way the body feels like it stays exactly where it is in the air but the suspension almost completely flattens the speed hump.

It's uncanny and almost unnatural, with just the tiniest change in altitude and no noise from the suspension.

It also manages the terrible narrow lanes of CBD thoroughfares with ease, the lane keep system letting you know if you're straying.

On to the motorway and you get a feel for its crushing performance. You won't hear much, though - the stereo's noise-cancelling system shuts out almost all tyre noise and consistent wind noise is largely banished, too.

I'm going to admit I gasped when I found some corners. Active suspension bodes well for the tricky stuff, as does the all-wheel steering. Both are exceptionally clever systems for making the car feel a lot smaller in town and in car parks but they're also really good if you want some fun.

But the way the rear-wheel steer adds agility to such a big car is hilarious and clever. While you can't quite chuck it around - and really, you're not buying an A8-sized car for that kind of nonsense - brisk progress is far from intimidating.

Now, obviously, a Ford Fiesta would drive away from the S8 in the really tight stuff but it would take some time to properly shake it. The colossal torque from the V8 hurls even this two-tonne-plus limo out of the corners in a most satisfactory manner.

It's surprisingly agile for a machine more than five metres long and two metres wide. If your passengers are corner enthusiasts, you'll all be having fun in near silence. It's oddly engaging to be moving at pace in such a hushed cabin.

Make no mistake, the GLE63 S is a big beast, but it certainly doesn’t act its size.

Firstly, the GLE63 S’s engine is an absolute monster, helping it to hunker down off the line and then charge on towards the horizon with serious vigour.

While there’s so much initial torque to begin with, you still get the added benefit of the ISG, which helps to eliminate lag as the new twin-scroll turbos spool up.

That said, acceleration isn’t always brutal, as the electronic stability control (ESC) is often quick to cut power when under full throttle in  first gear. Thankfully, engaging the ESC system’s Sport mode solves this issue.

This behaviour is somewhat ironic as the 4Matic+ system is seemingly never short of grip, with it's working hard to find the axle with the most traction, while torque vectoring and a rear limited-slip differential proportion torque from wheel to wheel.

Regardless, the transmission provides predictably smooth and predominantly timely gear changes, although they’re definitely not dual-clutch quick.

What’s more memorable, though, is the sports exhaust system, which keeps your neighbours relatively sane in the Comfort and Sport drive modes, but will drive them mad in Sport+, with hilarious crackles and pops heard loud and clear on the overrun.

It’s worth noting that while the sports exhaust system can be manually engaged in the Comfort and Sport drive modes via a switch on the centre console, it only makes the V8 rumble grow stronger, with the full effect only unlocked in Sport+.

Of course, there’s more to the GLE63 S experience, like the fact that  it somehow rides like a large SUV yet handles like a sports car.

The suspension’s air springs and adaptive dampers offer up a luxurious ride in the Comfort drive mode, with the GLE63 S wafting along with confidence. Not even its large-diameter alloy wheels pose too much of a threat to this quality on poorer country roads.

The ride is still more than liveable in the Sport drive mode, although the adaptive dampers become a  too firm in Sport+, with the ride becoming a little too jittery to be bearable.

Of course, the whole point of the adaptive dampers becoming progressively firmer is to help the GLE63 S handle even better, but the real revelations here are the active anti-roll bars and engine mounts, which effectively limit body roll to such a level that it’s almost imperceptible.

In fact, overall body control is impressive, with the GLE63 S not feeling like the 2.5-tonne-plus behemoth it is. It really has no right to attack corners the way it does, with the coupe feeling a touch tighter than the wagon, thanks to its 60mm-shorter wheelbase.

Further confidence is afforded by the sports brakes, which include 400mm discs with six-piston calipers up front. Yep, they wash away speed with ease, which is exactly what you’d hope for.

Also key to the handling is the electric power steering, which is speed-sensitive and has a variable ratio. It’s really quick in the wagon, and even more so in the coupe, thanks to its more direct tune.

Either way, this set-up is well-weighted in the Comfort drive mode, with plenty of feel and just the right amount of heft. That said, Sport and Sport+ make it gradually heavier, but neither make the driving experience better, so stick with the default setting.

Meanwhile, Noise, Vibration and Harshness (NVH) levels are pretty good, although tyre roar is consistent at highway speeds, while wind whistle is prominent over the side mirrors when travelling above 110km/h.

ANCAP awarded the second-generation GLE range its maximum five-star rating in 2019, meaning the new GLE63 S gets full marks from the independent safety authority.

Advanced driver-assist systems generously extend to autonomous emergency braking with pedestrian and cyclist 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, hill-descent control, park assist, surround-view cameras and front and rear parking sensors.

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

Audi continues to fail to match Mercedes move to a five year warranty, sticking with three year/unlimited kilometre cover. BMW is still doing it too, so maybe Ingolstadt and Munich are playing chicken. 

You can get a five-year service plan for the S8, coming out at $3990 for the duration.

As with all Mercedes-AMG models, the GLE63 S comes with a five-year/unlimited-kilometre warranty, which currently sets the standard for the premium market. It also comes with five years of roadside assistance.

Better yet, the GLE63 S’s service intervals are relatively long, at every year or 20,000km – whichever comes first.

It’s also available with a five-year/100,000km capped-price-servicing plan, but it costs $4450 in total, or an average of $890 per visit. Yep, the GLE63 S isn’t exactly cheap to maintain, but you expected that.