Mercedes-Benz GLS-Class vs Lexus GX

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 new Lexus GX 550 Sports Luxury looks fantastic and has enough mod cons to satisfy a family but it’s not as luxurious as you’d expect from a premium brand and the fuel economy and driving range will turn off some. But if you’re still interested, there’s a lot here that will make you happy and it’s one of the smoothest 4WDs I’ve driven.

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 new GX 550 looks massive and while it shares the same platform as the Toyota LandCruiser 300 series, it doesn't share all of its bulk. They both stand at 1980mm wide but differ on length (5015mm vs 4980mm) and height (1670mm vs 1950mm), respectively.

The new design is fabulously rugged but each body panel looks meticulously crafted and is just the right size. This just means the proportions look right and your eye sort of glides over the big body rather than stopping on any one feature.

But having said that, there are a lot of nice features to focus on, like the long LED headlights and rear strip light, auto-folding side steps, 22-inch alloy wheels and sharply styled rectangular side mirrors.

The tailgate window can also be opened if you need to pop something into the boot but don't want, or have the space, to open the tailgate itself.

The styling takes a minor nose dive once you hit the cabin, though, because it doesn't look as sumptuous as you'd expect in a premium SUV.

I love the utilitarian and military vibe of the vertical dashboard, chunky air vents and relatively small windscreen. It looks great but some trims are plasticky and the touchpoints, while soft, are not Lexus-plush.

However, the technology looks gorgeous with an integrated 14-inch multimedia display and a 12.3-inch digital instrument cluster. The fixed sunroof with its two settings (clear or opaque) is also a lovely feature.

But on a whole, the GX 550's European rivals outclass it with their flashier cabins.

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 of the new GX 550 is fairly practical with plenty of head- and legroom in each row (yep, even the third!). When you first hop in, it can feel a big snug on elbow-room but this feeling quickly dissipates.

Despite a 215mm ground clearance, access is pretty good for the front and middle rows due to the wide door apertures and side-steps. Third row access is a bit awkward for an adult but my eight-year old loved scampering back there this week.

The electric front seats are comfortable with their extra functions and I like the way the massage feature extends to the seat cushion as it limits fatigue on longer journeys. However, you sit on top of them rather sink into them which makes it feel a little trucky at times.

The wide middle row has a bench seat that will be comfortable for kids but an adult might get a sore behind on a long trip. The transmission tunnel also compromises foot room for adults but the seat is wide enough to make use of all three top-tether anchor points (there are ISOFIX mounts too).

It was a little bit of an effort to lift my big booster seat into the back because the GX 550 sits so tall but otherwise, there's plenty of room around a child seat for them not to feel like a sardine.

Individual storage is made up of a glove box that fits an owner's manual, a small shelf in the dashboard and a middle console that doubles as a cool box (mini fridge) and can fit up to four cans or bottles in it.

Each row gets four drinkholders and two USB-C ports but the front also enjoys a 12-volt socket and wireless charging pad. There's a 220V domestic plug port in the boot for larger appliances, too.

It's sometimes awkward to use the wireless charging pad because it's easy for your phone to slide around on it and it quite often disengaged from charging.

My son enjoyed all of the other amenities in the middle row, like the reading lights, climate control, two USB-C ports and retractable sunblinds and I applaud carmakers when they position rear directional air vents in the pillars and/or roof. It just makes it so much easier to cool down sweaty kids!

The 14-inch multimedia display has clear graphics and a responsive touchscreen. The layout is easy enough to get used to after spending some time with it and the sat nav is simple to use.

I like that the sat nav directions can be pulled into the 12.3-inch digital instrument cluster and head-up display.

There is a Lexus connected services app, which you get a three-year subscription to. It's easy to connect to the wireless Apple CarPlay and there is also wireless Android Auto.

The system also has Bluetooth and digital radio, which is a delight to use through the 21-speaker Mark Levinson sound system.

The cabin is rounded out by the well-shaped boot which has a massive 1063L of capacity when the third-row is folded. That's been more than enough for my family's needs this week and my German Shepherd was pretty comfy back there, too. The powered tailgate has a kick-function and there is a full-size spare wheel underneath the car.

The Lexus GX 550 shares the same platform as the recently introduced Toyota Prado but both models are now based on the same 'body-on-frame' platform shared by the beastie Toyota LandCruiser 300 Series. So it's bigger and features a more rigid chassis than before.

Surprisingly, that hasn't translated to a massive price tag for the GX 550 and you can pick up the flagship grade on test for this review for $128,200, MSRP.

Which sounds inexpensive when you compare it to the BMW X7 xDrive 40i M Sport which is priced from $171,300 MSRP but the Land Rover Defender 110 P400 X-Dynamic HSE is a lot closer at $128,815 MSRP.

The only issue here is that shared platform, because while they don't share the same powertrain, the flagship Toyota Prado Kakadu ($99,990 MSRP) is still almost $30K more affordable and boasts a similar equipment list. So, ask yourself, is it the brand and engine you're after or the new good looks?

The standard equipment is well-rounded with a 14-inch touchscreen media display with satellite navigation and wireless Apple CarPlay and Android Auto.

A fully digital 12.3-inch instrument cluster, colour head-up display, three-zone climate control and a 21-speaker Mark Levinson sound system round out multimedia requirements.

Other technology includes a digital rear view mirror, two USB-C ports in each row, a 12-volt socket, a 220-volt domestic outlet and a wireless charging pad.

There are two particularly handy features for families, the 'cool box' (basically a mini fridge) middle console and rear retractable sun-blinds.

The fixed panoramic sunroof features two settings allowing you to make it clear or opaque. The electric front seats feature heat, ventilation and massage functions and the rear outboard seats are heated as well. The third row electrically adjusts and there are multiple buttons throughout the car to access this feature.

Upgraded leather-accented upholstery is standard in the flagship grade and is available in three combinations. The Sports Luxury also features 22-inch alloy wheels, a full-size spare wheel and a powered tailgate with kick-function.

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.
 

All GX 550 grades share the same 3.5L V6 twin turbo-petrol engine which produces up to 260kW of power and 650Nm of torque.

This 4WD has high- and low-gearing, as well as a bunch of driving modes to suit most occasions, like 'Eco', 'Comfort', 'Sport' and 'Sport+'.

The 10-speed automatic transmission shifts through its gears smoothly and it always feels like it's engaged in the right gear. Which isn't always the case for a big SUV!

The Sports Luxury is fitted with a towing hitch and cover but unlike the base Sports grade which has a 3.5-tonne braked towing capacity, this model only has a 3130kg capacity which might not appeal to families with big toys to tow. 

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.

I didn’t have high hopes for fuel economy because the official combined (urban/extra-urban cycle figure is a hefty 12.3L/100km but after mostly open-road driving, with some urban stuff mixed in, my real-world average came in at 11.8L.100km! This figure is based on my actual km travelled (358km) and litres of fuel used (42.41L).

While I’m surprised by the fuel usage result, I wouldn’t say this car has good fuel economy compared to its diesel-powered counterparts but it’s not terrible!

The GX 550 has a relatively small fuel tank compared to its Toyota cousins at 80L and based on the combined fuel cycle, you’ll get a theoretical driving range of up to 650km.

Not all that great. Not for a big family mover and not if you’re typically driving in the city, where fuel usage will be a lot higher.

The GX 550 only accepts premium unleaded petrol (95 RON), too.

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.

Oh my goodness the Sports Luxury is a masterclass on 4WD refinement! You never feel the bulk or weight of this massive SUV when you’re driving it. The power delivery is effortless and there’s lots of grunt available when you hit hills.

The handling is also very good with responsive steering and enough road feedback as a driver to make you feel comfortable with what the car is doing. There is some roll in corners but it can tackle more corners at speed than I thought it would. 

The high driving position makes me feel like I can see a long way ahead yet while visibility is mostly good, it can be compromised when you have the side window shades and the third row headrests up. Which is why I love the digital rear view mirror.

Overall, ride comfort is good with forgiving suspension and low cabin noise, even at higher speeds. It’s pretty easy to chat with all rows and there’s not a lot of engine noise which adds to the refinement. I do like hearing a V6 rumble but that’s just a personal preference. 

I was a little worried about hitting my local Westfield car park but this is a nimble SUV to manoeuvre and parking it is a breeze with the 360-degree camera system and parking sensors. 

The new GX 550 hasn’t been tested by ANCAP and is unrated but its cousin, the Toyota Prado, which shares the same platform just achieved a maximum five-star rating from assessment in 2024. It's fair to expect a good result for this model.

Overall, the Sports Luxury has a long list of standard safety equipment and features nine airbags which is good for a family SUV. 

Safety equipment includes adaptive cruise control, lane departure alert, lane keeping aid, traffic sign recognition, emergency steering assist, driver monitoring, safe exit assist, emergency call functionality, blind-spot monitoring, rear cross-traffic alert and tyre pressure monitoring.

The GX 550 has autonomous emergency braking (AEB) with pedestrian, cyclist, motorcyclist and junction turning assist.

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.

Lexus offers the GX 550 with a five-year/unlimited km warranty, which is fairly standard compared to its Euro rivals.

You get five years capped-priced servicing which costs $5950 but the servicing schedule is a bit of a bear at every six months or 10,000km, whichever occurs first.