Mercedes-Benz GLS-Class vs Lexus GS350

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…

Weirdly, given all the good things I've had to say about the GS F Sport, it doesn't quite hang together. It's missing that certain something the Europeans have in their chassis, particularly the BMW 5 Series, and with ageing interior tech, it's struggling to keep up.

It's a car built for specific tastes, and they're more California than Straya. And that's perfectly okay, but unfortunately, that doesn't translate to a stampede of buyers. Having said that, none of its German rivals (or its beleaguered Japanese counterpart, Infiniti) could claim wild sales success either.

The GS is a terrific car, underrated but also just not quite there for my taste. The GS F, though, that's another thing altogether.

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.

The GS is ageing well, but it's still a bit heavy-handed around the headlights and a little on the slabby side along the flanks. It doesn't look poised for action, even with the F Sport additions, but nor does it look frumpy, mostly due to the whopping blacked-out spindle grille, a Lexus signature. 

The rear end is good looking but a bit bluff, again neither surprising or delighting.

Little has changed inside, but it's still a very nice cabin, and always will be apart from a couple of clangers (the gear shifter looks super-cheap). 

What's more, it's welcoming, lots of very nice materials, comfortable, seats - it's exactly what it needs to be. Whatever you might think of the looks, one thing is absolutely certain - if anyone builds cars better than Lexus, it's a very, very short list.

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.

Being a big car, there's plenty of room inside. Four passengers will be very comfortable although rear legroom was a bit on the skinny side given the car's size.

The cabin contains a good-sized console bin, four cupholders and each door pocket into which you could conceivably slot a bottle.

The 520-litre boot is a useful shape, with a sensible load height and a space-saver spare under the floor. The 5 Series and E Class both best the Lexus by 10 litres, so the GS isn't far off the norm.

We had the pleasure of the GS 350 F Sport for the week, which is well over $10,000 cheaper than the Luxury and is therefore the 'default. If you're not sure what F Sport means, it's Lexus' answer to an M Sport or AMG pack, without all the high-powered engine shenanigans to go with it. If that's what you're after, the V8-powered Lexus GS F is definitely for you.

Starting at $95,300, the F Sport has a spectacular standard features list - 17-speaker stereo, 19-inch alloys, variable-geared four-wheel steer (!), adaptive suspension, dual-zone climate control (with moisturising function), hectares of leather trim, head-up display, electrically-operated heated and ventilated front seats, rear sunshade, F Sport instrument screen, auto LED headlights, keyless entry and start, sat nav, front and rear parking sensors with around-view cameras and a space-saver spare.

The media system is run from Lexus' 12.3-inch screen embedded in the dashboard and controlled from an infuriating console-mounted mouse-clicker with a couple of shortcut buttons. It really is spectacularly irritating and made worse by the rotary dial stationed next to it that acts as the drive mode selector. Why not use that instead? 

As ever, the system is mildly baffling to use and hard to look at, but the sound is absolutely lovely from the Mark Levinson-branded speakers. Lexus is persisting with a DVD player but it also has DAB+.

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.
 

Lexus fits a 3.5-litre (2GR-FKS) naturally-aspirated V6, delivering 232kW/380Nm to help shift the 1745kg GS. Power goes to the rear wheels via an eight-speed automatic. Lexus claims the sprint from 0-100km/h is completed in just six seconds.

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.

A real world 13.7L/100km is a solid miss of the claimed 9.3L/100km, which itself is hardly earth-shattering. It's a big heavy car and that's the penalty. It drinks fuel fast, so the 66-litre fuel tank does drain quickly and it's worth knowing you have to fill it with the 95 RON or better.

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.

There are things you expect in a Lexus. Quietness. Composure. Smoothness. The GS delivers all three of those things effortlessly. But it has a few extra things in its bag that I can't say I was expecting.

For a start, the 3.5-litre V6 moves the car without any carry-on and in doing so, I was constantly amazed at how quickly the speed in the head-up display reached the posted limit. It just doesn't feel or sound like a six second car, but there you are. The transmission is virtually faultless, the engine sound distant and refined, the power impressive.

It's a heavy car, no question, but two things work to make it feel much lighter. First - and it doesn't matter which mode you choose - the adaptive suspension somehow knocks about 200kg out of how heavy the car feels. The brakes, while a little soft on pedal feel when you first step on them, are very effective and again help to make the car feel lighter than it is.

The four driving modes are quite distinct. As usual, Eco makes everything soft and doughy or as I prefer to say, unpleasant. Normal is great for every day, with just the right throttle response and steering weight.

Moving to sport ups the aggro slightly while Sport+, while never harsh, firms everything up to the point where it starts to feel like a different car. Sport+ makes the car feel race-car pointy, the suspension holds the body in check and the power seems readily available without jerky progression

The all-wheel steer is a big part of the change in feel. It's is especially sharp in Sport+ mode. The steering's gearing changes up quite a bit, meaning a lot less steering lock required for your favourite hairpin bend. Of course, at real speed it all calms down because neither you nor Lexus are fond of sneezy lane-changes or Armco-swiping. At first I thought it just made the big car feel a bit too nervous but as I got used to it (and was able to dial it down by switching back into a less racy mode) I found it fun but a little bit out of character with the car itself.

And just because it's the F Sport, that doesn't mean it can't do all the things you'd expect from a Lexus. You can still waft, you can still creep up on people and it's really very comfortable when you're cruising or stuck in traffic. 

The GS scores 10 airbags, ABS, stability and traction controls, blind spot monitoring, rear cross traffic alert, forward AEB, active cruise, auto high beams and lane departure warning with lane keep assist.

The GS doesn't have an ANCAP or Euro NCAP rating while the USA's IIHS (Insurance Institute for Highway Safety) rating is good for each key crash-worthiness measure. The IIHS suite of tests is quite rigorous but differ from our ANCAP/Euro NCAP standards.

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.

There's one area where Lexus smashes the Germans and that's after-sales. While the warranty is hardly ground-breaking at four years/100,000km and service intervals are reasonable at 12 months/15,000km, it's how it all comes together.

For the duration of the warranty, when the car needs a service, Lexus will either come and get it then return it to you, or give you a loan car. Anecdotal evidence suggests this continues long after the warranty runs out. Like, 10 years after the warranty runs out. 

This is a small thing, but if there's one thing I hate about car ownership, it's the servicing experience. If I was a betting man, I'd dare you to find someone who genuinely has a problem with Lexus after-sales care.

On top of that, you get a generous roadside assist package for four years.