Mercedes-Benz GLS-Class vs Audi Q8

What's the difference?

The GLS63 is an intimidating beast from afar, but it rewards its occupants in almost every way. Yep, there really isn’t a box it doesn’t tick without serious compromise, such is its breadth of capability.

If there was ever a Swiss Army Knife of cars, the GLS63 is definitely a contender for the title, one that makes it very hard to wipe the smile off your face. Just make sure you can fit it in your garage first…

The updated Audi Q8 60 TFSIe quattro S line still looks good inside and out. It fits a family comfortably without feeling too big and there’s enough here to satisfy those who like the luxury features. 

It's price tag will hurt it but the improved power outputs and driving range is a big plus and makes the plug-in hybrid powertrain make more sense.

If the GLS63 was a Marvel superhero, it would undoubtedly be the Hulk. Simply put, it has road presence like few others. In fact, it’s frankly menacing.

Of course, the GLS is already pretty intimidating due to its sheer size and blocky design, but the GLS63’s full-fat AMG treatment takes it to another level.

Naturally, the GLS63 gets an aggressive body kit, with its purposeful bumpers, side skirts and rear spoiler serving as instant reminders of what you’re dealing with, but it’s AMG’s signature Panamericana grille insert that really hammers home the point.

Around the side, the GLS63’s 22-inch alloy wheels with staggered tyres (front: 275/50, rear: 315/45) make their presence known, positioned below the wheelarch extensions.

That said, some fun’s also had at the rear end, where the GLS63’s diffuser element integrates the foreboding sports exhaust system with quad tailpipes very neatly.

The focused Multibeam LED headlights also look the part, while the opposing LED tail-lights tie everything together outside quite nicely.

Inside, the GLS63 stands out from the GLS crowd with its sports steering wheel with Dinamica microfibre accents, and multi-contour front seats, which are covered in Nappa leather alongside the armrests, dashboard and door shoulders and inserts.

Of note, the doors bins are unfortunately of the hard plastic variety, which is very disappointing in a vehicle that costs this much. You would expect that cow hide would also been applied to them, but alas it isn’t.

The GLS63’s black headliner serves as an obligatory reminder of its sporting intent, and while it makes for a dark cabin, metallic accents are prominent throughout, while the optional trim (our test vehicle had carbon-fibre) mixes things up, alongside the ambient lighting.

And let’s not forget the GLS63 is still loaded with plenty of cutting-edge technology, including a pair of 12.3-inch displays, with one the central touchscreen and the other the digital instrument cluster.

Both are powered by Mercedes’ class-leading MBUX multimedia system and feature Apple CarPlay and Android Auto support. This set-up arguably remains the best there is today thanks to its speed and breadth of functionality and input methods.

When it comes to style, the Q8 60 TFSIe quattro S line has it in spades. Featuring a design that looks athletic with its long lines and wide stance, you'll always be proud to hop into it.

Red calipers now come standard and they look awesome on the optioned 22-inch alloys. The update sees a redesigned front with new grille and reshaped matrix LED headlights and a 2D badge design.

While SUV coupes aren’t usually my jam, the Q8 manages to tick the 'sexy' box.

The interior is honestly the same and only die-hard fans will notice the new menu screens on the multimedia system. The cabin is a fine example of what a luxury SUV should look like because its polished, well-built and sumptuous but it has the classic Audi edge, so there is still a sporty vibe going on.

The panoramic sunroof adds some airiness to the otherwise dark cabin and the Valcona leather upholstery is liberally splashed about, so most of what you touch feels premium and soft.

Measuring 5243mm, 2030mm wide and 1782mm tall with a 3135mm wheelbase, the GLS63 is an upper-large SUV in every sense of the term, which means it’s also very practical.

For example, cargo capacity below the load cover is decent, at 355L, but stow the 50/50 power-split-folding third row via the boot and it’s very good, at 890L, or drop the 40/20/40 power-split-folding middle bench, too, and it becomes a cavernous 2400L.

Better yet, the boot’s aperture is almost square, and its floor’s flat, while there’s no load lip to contend with, making loading bulkier items even easier. Up to four tie-down points are also on hand (depending on seating configuration) to secure loose cargo.

Under the false floor is the space-saver spare, which is to be expected, but what isn’t expected necessarily is the fact there’s also enough room there for the cargo cover when it’s not in use, which would be the case if six or more passengers are regularly onboard.

Moving into the power-sliding second row, the GLS63’s practicality is once again brought to the fore, with up to six-plus inches of legroom available behind my 184cm driving position.

There’s also two inches of headroom with the panoramic sunroof in situ, not to mention just enough toe-room. The GLS63’s small transmission tunnel and sheer width also mean three adults can be seated on the middle bench with few complaints.

Amenities-wise, the second row has map pockets on the front-seat backrest and a small fold-down cubby below the rear climate controls, with it containing two slots for smartphones and a pair of strategically placed USB-C ports.

The rear door bins can take one large bottle each, while a fold-down central armrest is also on hand, featuring a shallow tray and retractable (and flimsy) cupholders.

Alternatively, the $2800 Rear Seat Comfort Package fitted to our test vehicle subs in a tablet that can control the multimedia system, a wireless smartphone charger and a small cubby into the former, as well as a heated/cooled cupholder atop the rear of the centre console.

In the third row, it’s not quite as roomy if you’re an adult. With the middle bench in its most accommodating position, my knees still brush up against its backrest, which is to be expected given it’s primarily designed for children. I also have an inch of headroom there.

Nonetheless, getting in and out of the third row is relatively easy as the power-operated middle bench tumbles forward and provides just enough space to make entry and exit somewhat graceful.

When seated, rear occupants are treated to two USB-C ports and one small cupholder each, so they’re arguably taken better care of than those in the middle.

Child seats are well and truly accommodated, with four ISOFIX and five top-tether anchorage points fitted across the second and third rows, although the latter will inevitably prove to be a much tighter fit.

The driver and front passenger are still taken care of, with a front cubby taken up by two heated/cooled cupholders, a wireless smartphone charger, two USB-C ports and a 12V power outlet, while their door bins take one large and one small bottle each.

In-cabin storage options include the large central storage bin, which hides another USB-C port, while the glovebox is on the smaller side, with about a third of it taken up by the fragrance, which is pumped into the cabin to ensure the interior always smells its best.

The cabin offers plenty of space for passengers and you never feel like you're jostling for elbow room unless there's three adults across the rear seat. Comfort is high with ergonomic seating up front with plenty of adjustment and functions. The rear seat has long bases and the seat backs can recline.

Individual storage leaves a little to be desired for the class and the glove box shoulders most of the burden up front as the middle console is really just a shallow shelf large enough for a wireless charging pad and keys or a chapstick.

Each row gets a couple of cupholders and drink holders, and the rear map pockets round out back-seat storage.

Because of the PHEV powertrain, the 60 TFSIe quattro S line has the smallest boot capacity in the line-up at 505L but this is still more than enough for a decent road trip or grocery haul.

The wide boot aperture, level loading area and powered tailgate add some convenience, as does the 40/20/40 split fold on the rear seats.

Access for each row is solid with wide door openings, low seat positions and 205mm ground clearance. Although, the doors have to been slammed shut for them to close properly and this annoyed everyone in the family. You can spring for a soft-close door feature for $1500 and, honestly, it would be worth it.

The 10.1-inch touchscreen multimedia system is logically laid out and the graphics look great. It has haptic feedback which my husband didn’t love as it made it hard to select things on a bumpy road. You also get built-in sat nav, wireless Apple CarPlay and Android Auto. Other than the occasional lag with the CarPlay connecting upon start up, it's all simple enough to use.

Charging options are good with two USB-C ports in each row and the front also gets a wireless charging pad. The big 12.3-inch digital instrument cluster looks great but it can be annoying to find information on it or personalise it.

There are three Q8 grades before you hop into the flagship SQ8 performance model, and the variant on test for this review sits second from the top.

The mid-life refresh sees pricing increased across the entire range and adds over $1700 to the (already steep) $154,284 MSRP price tag.

Compared to its plug-in hybrid rivals, the BMW X5 xDrive50e and Volvo XC90 Recharge Ultra T8, the 60 TFSIe quattro S line slides in as the most expensive.

Our test vehicle has also been fitted with a few extra items like 22-inch alloys, metallic paint and a luxury seat package, which adds ventilation function to the front seats and heated rear outboard seats. It does tack on $9900 to the overall price tag, though.

The 10.1-inch multimedia system remains and while it sits on the smaller end compared to some of its rivals now, it does get an updated layout and apps for 2025.

Other standard equipment includes a panoramic sunroof, matrix LED headlights, heated side mirrors with memory, keyless entry and start, a powered tailgate, heated front seats, electric lumbar support, three-zone climate control, electrically adjustable steering wheel, electric auto cargo cover, and a tyre repair kit.

The technology is the standout with a 17-speaker Bang & Olufsen sound system, wireless Apple CarPlay and Android Auto, digital radio, as well as built-in satellite navigation, a 12.3-inch digital instrument cluster and colour head-up display.

You also get an Audi Connect plus app which allows remote access for security and assistance services including car finder with remote signal, remote lock and unlock, emergency call, and online roadside assistance.

Does the PHEV Q8 offer good value? Value is relative, the features list is fairly robust but it’s hard to ignore that this PHEV sits $10K above its internal combustion siblings.

The GLS63 is powered by a familiar 4.0-litre twin-turbo V8 petrol engine, with its version producing a thumping 450kW of power at 5750rpm and 850Nm of torque from 2250-5000rpm.

This unit is mated to a nine-speed torque-converter automatic transmission and AMG’s fully variable 4Matic+ all-wheel-drive system with torque vectoring and a rear limited-slip differential.

This set-up also features Mercedes’ EQ Boost 48V mild-hybrid system, which actually gives a 16kW/250Nm electric boost in short bursts, such as when accelerating off the line.

Speaking of which, the GLS63 sprints from a standstill to 100km/h in just 4.2 seconds, while its top speed is electronically limited to 250km/h.
 

The Q8 60 TFSI e is AWD and has a 3.0-litre V6 turbo-petrol plug-in hybrid powertrain for a combined power output of 360kW and 700Nm of torque.

The power output has increased by 20kW with the mid-life refresh and that shaves 0.4 seconds off the 0-100km/h sprint time bringing it down to just 5.0 seconds. So it’s a quick and powerful SUV.

The powertrain is paired with an eight-speed automatic transmission which is mostly smooth and the switch between petrol and electric is fairly seamless.

As far as plug-in hybrids go, everything seems to work well here.

The GLS63’s fuel consumption on the combined-cycle test (ADR 81/02) is 13.0L per 100km, while its carbon dioxide emissions are 296 grams per km. All things considered, both claims are unsurprisingly high.

In our real-world testing, we averaged a fearsome 18.5L/100km over 65km of driving, split between highways and country roads, so not your usual mix. A very heavy right foot definitely influenced that result, but don’t expect to do too much better in a normal run.

For reference, the GLS63’s 90L fuel tank can be filled up with 98RON petrol at a minimum.

The mid-life update sees a larger 25.9kWh lithium-ion battery which improves the electric driving range by 27km, bringing it up to 74km overall. This still falls short of its direct rivals but it’s an improvement for efficiency because it’s now more than enough range if you’re just doing the school runs and some errands around town.

The Q8 60 TFSIe has a Type 2 charging port and like most plug-in hybrids, lacks a CCS enhancement, so you have to make do with AC charging options with this one. On a 7.4kW AC charging system you can go from 0-100 per cent in three hours and 45 minutes but if you’re using just a standard house plug port, it will take a few hours more. It's best to leave it overnight.

Audi throws in three charging cables, including a 240-volt domestic charger but you have to pay extra for a wall-mounted box.

The official combined fuel cycle is a low 1.8L/100km and like all plug-ins the best efficiency will be achieved if you charge it often. After charging almost every day and doing a mix of open road and urban driving, my real-world usage has popped out at 7.7L/100km, which isn’t as good as I was hoping but it’s not terrible. I would expect the efficiency to drop on longer trips.

The Q8 likes to drink the good stuff and Audi recommends a minimum 95 RON unleaded petrol to be used for this grade.

Frankly, the GLS63 has absolutely no right being as capable as it is. It’s a really big bus that’s legitimately convinced it’s a sports car half its size.

Being a GLS variant, the GLS63 has independent suspension consisting of four-link front and multi-link rear axles with air springs and adaptive dampers, but its party trick is the addition of active anti-roll bars.

In what feels like magic, the GLS63 is simply not intimidated by corners, despite having massive dimensions and a considerable 2555kg (kerb weight) to deal with.

The active anti-roll bars make the GLS63 so much easier to drive fast through the twisty stuff, almost eliminating body roll, taking one key variable out of the equation for the driver. Active engine mounts are also fitted, helping to settle things even further.

The electric power steering on hand is also good. It is speed-sensitive and has a variable ratio, which basically makes the set-up more direct when it needs to be. It’s typically light in hand, too, until one of the sportier drive modes is engaged and extra heft is added.

So, handling is scarcely believable, which means the ride must be compromised, right? Yes and no. With the adaptive dampers in their softest setting, the GLS63 is very compliant. In fact, we’d say it feels luxurious when compared to other high-performance SUVs.

That said, our test vehicle was fitted with the optional 23-inch alloy wheels ($3900), which look the part but expose sharp edges and other road imperfections, not to mention generate noise easily heard inside. Naturally, feedback is exacerbated in the sportier drive modes.

Anyway, there’s more performance, and the GLS63 has the rest in spades. Its engine is a powerhouse in every sense of the word. It’s so powerful, in fact, that it hilariously hunkers down off the line or when suddenly accelerating at low speed.

Thanks to the mild-hybrid system, wads of torque is available from the get-go, making for a highly responsive driving experience, even in those rare moments when the engine isn’t on song.

While not as characterful as some of the other members in the 63 series, the GLS63 still makes some thoroughly entertaining noises, with its sports exhaust system popping like mad while on the overrun.

All of this ability is very well and good, but you need to be able to pull up quickly, and the high-performance braking package (400mm front and 370mm rear discs with six-piston fixed callipers and single-pot floating stoppers respectively) mercifully does exactly that.

The Q8's athletic looks are matched by its on-road handling. The power has a hefty kick that’s effortlessly delivered once you’re up to speed. It did have a few confused moments when I had to accelerate quickly from a full stop - the lower gears didn’t immediately engage and I got a proper bunny hop but it was short lived and for the most part the powertrain delivers the goods.

The adaptive air suspension makes for a comfortable ride despite the massive wheels and you can comfortably cruise around town or the highway without much jostling.

Cabin noise is minimal around town but you get a low hum of road noise at higher speeds. Overall, it's still a refined cabin space to spend a lot of time in.

I do miss hearing some of the engine thrums though because even when the battery is depleted, you don’t get a lot of engine feedback. It certainly adds to the refinement but it loses some of the fun.

The higher driving position feels comfortable and visibility is quite good. Steering is responsive and feels sporty with lane changes but its 13.3m turning circle lets it down in car parks.

The 360-degree view camera system is clear and this has multiple parking sensors. In theory parking should be easy but again, until you get used to that bigger turning circle it can feel clumsy in smaller spaces.

The PHEV Q8 variant is unrated with ANCAP as it’s not covered by it’s siblings' five-star rating from 2019, but it does have a lot of standard safety features like eight airbags, including side chest airbags for the front and rear passengers. Surprisingly, it misses out on a front centre airbag though. 

A standout feature is the safe exit assist which will delay your door from opening if it detects a car or cyclist. Always a handy thing when you have a kid like mine who can carelessly throw open their door.

There is also a ‘pre-sense’ feature where the car detects that you’re approaching traffic at lights or a roundabout and it will automatically start slowing down for you, which I quite liked.

Other standard features include adaptive cruise control with stop and go, lane keeping aid, lane departure warning, blind-spot monitoring, forward collision warning, rear cross-traffic alert, driver attention monitoring (sound and visual alerts), 360-degree view camera system, front and rear parking sensors, tyre pressure loss indicator, intelligent seatbelt reminders, first aid kit, hi-vis vests and a collapsible warning triangle.

The autonomous emergency braking (AEB) has car, cyclist and pedestrian detection and is operational up to 85km/h (up to 250km/h for cars).

There are two ISOFIX child seat mounts and three top tether anchor points. The rear seat is wide enough to accommodate three child seats side by side.

The safety systems feel well-calibrated and are not intrusive for daily driving. In a world when cars seem to chime an alert for everything, this is a welcomed plus.

As with all Mercedes-AMG models, the GLS63 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.

The GLS63’s service intervals are relatively long, at every 12 months or 20,000km (whichever comes first). Better yet, it’s available with a five-year/100,000km capped-price servicing plan, but it costs $4450.

Audi offers the Q8 60 TFSIe with a five-year/unlimited kilometre warranty and the battery is covered by an eight-year/160,000km warranty which are all pretty standard terms compared to its rivals.

There is a standard five-year servicing package that costs $3570 and servicing intervals are spaced at every 12 months or 15,000km, whichever occurs first. However, if you purchase the Audi Advantage Package you add a further two years of coverage to the warranty, roadside assistance and servicing, which is pretty good for the class.