What's the difference?
The price of fuel probably doesn't feature too highly on a 'Things to Worry About' list for people who can afford a luxury SUV. If you're spending more than $130,000 on a vehicle then, chances are, you glide on through service station forecourts with nary a concern about the cost of go-juice, but nevertheless Lexus has introduced its diesel-sipping LX 450d to the ever-growing arena of upmarket wagons. It has a claimed fuel consumption of 9.5L/100km – using just under five litres per 100km less than the eight-seater LX 570, its petrol stablemate.
But does this five-seater up-scale offering deliver much in the way of anything different to any other pricey people-mover, other than the fact it's an oil-burner? Read on.
The ‘Upper Large SUV over $120K’ segment of the Aussie new-car market is what you might call the top end of town, not only in terms of the extravagant models available but also their purchase prices, which stretch well into six figures and require monthly lease payments that rival home mortgages.
It’s where you’ll find some of the most prestigious marques in the automotive world including Rolls-Royce, Aston Martin, Bentley, Ferrari, Lamborghini, Range Rover, Lexus and BMW. And, of course, Mercedes-Benz with its big GLS which represents the flagship of the German manufacturer’s SUV fleet.
It was given a refresh in 2023 with cosmetic and multimedia upgrades along with powertrain enhancements, but there have only been minor changes since then. We were recently entrusted with the keys to the latest GLS to see if the ‘S-Class of SUVs’ leaves any room for improvement.
If you're in the market for the best-of-the-best SUV wagon, then you could do a lot of worse than get in a LX 450d. It looks good, is packed with standard features and is supremely comfortable. The 450d also has an suite of safety tech worthy of the hefty price-tag and it works well as a daily driver and has plenty of touring potential, even though we doubt it'll ever get anywhere near achieving those claimed fuel-consumption figures with real-world usage. Sure, you could instead climb in a second-hand, well-looked-after, never-been-off-road LandCruiser 200 Series and spend the money you save, by not buying this new Lexus, on aftermarket and camping gear, camping fees and also hiring a team of four people to follow you on mopeds everywhere and constantly tell you what a great driver you are – but that's not the point with vehicles of this ilk. They may not be aimed at hard-core off-roading buyers, but they are cushy, classy, and cityified – and, in that respect, they're incredibly well-built for purpose.
The GLS450d impresses as an entry-level grade, as it’s a more family-friendly allrounder than the specialised AMG and Maybach variants. Its combination of a torque-rich diesel 48V hybrid drivetrain, air-cushioned suspension and plush interior are as well suited to luxury urban travel as they are to grand touring, where its heavy towing and generous load-carrying capabilities can shine. Whether it’s worth around $200K drive-away, only those who shop at the top end of town can decide.
It has that signature Lexus jagged space-age grille, chunky shoulders and beefy back end that suit a luxury SUV dreamed up by folks craving a significant presence and plenty of attention for their product.
Bulky side-steps, an upswept raked profile, scalloped side panels and moon roof all top what is a cool combination of eye-friendly design factors. It's a slick mix of low-level cool and high-end style.
Take a look for yourself and make up your own mind whether you like it or not.
This is an imposing vehicle in extravagant S-Class tradition, riding on an expansive 3135mm wheelbase and stretching more than 5.2 metres (5215mm) long and more than 2.0 metres (2030mm) wide with a turning circle that's nudging 13 metres.
However, it’s just under 1.8 metres (1798mm) tall, so there’s no clearance issues when accessing multi-storey carparks. And with its side-steps (or ‘running boards’ in nostalgic Benz speak) most adults can step rather than climb aboard, although passengers of shorter stature during our test noted that assist handles on the A and B pillars would be handy.
Central to its sophisticated chassis design is adaptive air suspension, which uses a pneumatic or ‘airbag’ form of springing with adaptive damping to continuously optimise ride comfort and handling response according to road conditions and driving dynamics (see Driving).
The GLS’s styling is clean and uncluttered with tasteful restraint evident in its chrome and satin-chrome highlights, yet it projects a majestic quality with its prominent four-louvre grille and elegantly spoked alloy wheels.
The spacious and sumptuous seven-seat interior is visually pleasing and practical, with a subtle blend of surface treatments, contrasting tones, lots of soft-touch surfaces and exposed stitching. This is combined (thankfully) with physical dials, switches and ‘piano key’ buttons to control numerous interior functions, in preference to distracting touchscreen prompts.
It certainly feels like Lexus designers and engineers have maximised every last millimetre of interior space; there is stacks of room inside with plenty of real-world usable storage spaces, including cup-holders, door pockets and spots for keys, phones and other stuff.
The heated steering wheel, stylish analogue clock, wireless charger, Lexus climate concierge (coordinating all four-zone temperature controls), cavernous centre-console cooler box, and rear-seat entertainment system are all nice touches but pretty much assumed at price-points lower than this one.
The 12.3-inch high-definition media touchscreen is clear and bright and easy to operate, but the Remote Touch Interface, the control near the shifter, is very annoying to use. The toggle/selector is too sensitive, skipping past your actual choice over and over again, while you try to manipulate it just so, so it lands on the option you wanted.
The second-row seating is plush and the seat sections are easily slid forward and tilted.
Lexus claims the 450d offers 909 litres of cargo space if there are five occupants; and 1431 litres if there are only two occupants. If you have some casual weekend touring in mind, with a spot of camping, then this Lexus should cope with your gear, no worries.
Although it has a hefty 2655kg kerb weight, our test vehicle’s 3420kg GVM rating provides a useful 765kg of load capacity, which should comfortably absorb the combined weight of up to seven occupants and light luggage. Or with the third row of seating folded, five occupants and heavier luggage.
It’s also rated to tow up to 3500kg of braked trailer and with its sizeable 6920kg GCM (or how much weight it can legally carry and tow at the same time) it can carry its maximum load while towing its maximum trailer weight.
So, that’s commendable practicality, given it would be well suited to owners that need to tow large caravans, boat trailers, horse floats etc in style without having to compromise much (if at all) on either passenger numbers or luggage capacity.
Driver and front passenger space and comfort is exceptional, as you’d expect. Storage includes a large glovebox plus a bottle holder and bin in each door. The front of the centre console has two USB-C ports, wireless phone charging and heated cupholders, while the rear of the console has a large storage box with a third USB-C port and padded lid that doubles as a comfy elbow rest.
Even tall passengers in the second row of seating enjoy spacious comfort, given I’m 186cm and with the driver’s seat set in my position I have ample knee clearance, foot room and head space.
However, the central passenger must contend with a transmission tunnel in the floor and shoulder room would be squeezy for three large adults, which is okay for short trips but a maximum of two would be ideal for longer journeys.
The rear of the centre console also treats second-row passengers to a pair of USB-C ports, adjustable air-vents and a control panel that allows independent climate adjustment.
There’s also a large bin/bottle holder in each door plus storage nets on each front seat backrest. The centre seat backrest folds flat to allow long items (skis etc) to slot between the outer backrests. And it also serves as a fold-down armrest, containing two cupholders and a lidded slimline compartment that’s ideal for hidden phone storage.
The third row is uncommonly spacious, even for tall people, with padded armrests on each side containing cup holders and twin USB-C ports.
The carpeted rear luggage area has four load-anchorage points, a first aid kit and 12v socket. With the third-row seats upright it offers 355 litres of load volume, which increases to 1350 litres with the third row folded and 2400 litres (or 2.4 cubic metres) with both the second and third rows folded.
Price as tested on our five-seat LX 450d is $136,000. The base RRP is $134,500 and our Lexus had premium paint (Sonic Quartz), which adds $1500; no other options were fitted.
It is absolutely packed to the rafters with high-quality stuff, which is no surprise really because, at this price, you’d expect nothing less. Standard features include a 12.3-inch high-definition screen with nine-speaker, seven-channel audio system (with “digital sound processing”), satellite navigation, and four-zone climate control air-conditioning with climate concierge function and nanoe technology (claimed to purify the air and moisturise hair and skin, according to Lexus). It also has heated front seats, leather-accented trim, a wireless phone charger, cool box, rear-door sunshades, 20-inch alloy wheels with 285/50R tyres, tyre-pressure warning, LED headlamps, daytime running lamps and sequential turn signals.
There are seven exterior colours and two leather-accented interiors from which to choose.
The LX 450d does not have any enhancement packs.
Our Polar White test vehicle, which is the base grade in the three-tiered GLS range, comes standard with a 3.0-litre inline six-cylinder turbocharged diesel engine with 48V mild hybrid technology, nine-speed automatic transmission, permanent all-wheel drive and active air suspension for a list price of $189,100.
This pricing is higher than comparative entry-level grades offered by the two marques which dominate sales leadership in this segment, comprising the BMW X7 xDrive40d M Sport ($179,500) and Lexus LX500d AWD ($158,700).
The GLS450d’s standard features include 22-inch AMG alloy wheels with Continental 325/40 R22 tyres and a collapsible spare, ‘AMG Line’ body styling enhancements, aluminium-look illuminated side-steps with non-slip rubber studs, multi-beam LED headlights and more.
Step inside the keyless interior and you’ll find ‘Hey Mercedes’ voice activation, fingerprint scanner (which memorises individual comfort settings for up to seven users), panoramic sunroof, heat-insulating dark-tinted rear privacy glass and the ‘Premium Plus Package’ that includes heating/cooling for the front seats, heated rear seats, head-up display, separate front/rear climate control zones, heated cupholders and more.
There’s also a concert hall-like Burmester surround sound system controlled by a central touchscreen with digital radio and Apple CarPlay and Android Auto connectivity, plus wireless phone charging, multifunction Nappa leather sports steering wheel and USB ports front and rear.
Driver assistance includes the ‘Parking Package’ (360-degree camera, active parking assist and transparent bonnet), ‘Mirror Package’ (auto-dipping rear-view mirror and electric folding door mirrors with puddle lamp projection of the brand logo) and ‘Driver Assistance Package’ (blind-spot assist, exit warning, speed sign recognition, lane keeping etc) all included as standard equipment.
Of course, Mercedes-Benz offers numerous extra-cost options including a 3500kg towing package plus interior, exterior, suspension and wheel enhancements (including Nappa leather trim) for those who want their GLS with the lot, which can easily push the list price beyond $200K.
The Lexus LX 450d has the LandCruiser's 4.5-litre twin-turbo direct-injection V8 engine, producing 200kW@3600rpm and 650Nm@1600-2800rpm. All of that power and torque arrives evenly and smoothly, helped no end by a slick six-speed sequential-shift transmission.
It has a full-time 4WD system, dual-range transfer case and off-road tech that includes multi-terrain anti-skid brakes, crawl control and a four-camera multi-terrain monitoring system with back guide and panoramic view.
The GLS450d comes standard with a 3.0-litre turbocharged inline six-cylinder diesel producing 270kW of power at 4000rpm and 750Nm of torque between 1350-2800rpm.
This is paired with a 48V mild-hybrid system comprising a 48-volt battery (charged by regenerative braking) and an integrated starter-generator which provides both seamless engine stop-start and up to 15kW/200Nm of extra power and torque during acceleration.
A nine-speed torque converter automatic provides the choice of manual shifting using the steering wheel-mounted paddles, along with several selectable drive modes.
The active all-wheel-drive system continuously adjusts the engine’s torque delivery between front and rear axles (and individual wheels as needed) to maintain optimum traction and handling.
Lexus claims the LX 450d will achieve a 9.5L/100km figure from combined-cycle driving (that's 4.9L/100km more frugal than the LX 570 is capable of). Lexus reckons, based on that figure, that the diesel LX has a potential range of almost 1000km on a full tank (93 litres) of fuel.
We recorded 12.7L/100km during daily driving (city and suburbs) and 13.5L/100km with some light off-roading thrown into the drive mix.
Mercedes-Benz claims official combined consumption of 7.8L/100km and the dash display was showing 9.0 when we stopped to refuel at the completion of our 368km test, which included the usual mix of suburban, city and highway driving with up to five passengers at times and light luggage.
Our own figure, calculated from fuel bowser and tripmeter readings, was close at 9.5 which is outstanding sub-10L/100km economy for such a substantial vehicle in mostly metropolitan use. Therefore, based on our own consumption figure, you could expect a real-world driving range of around 950km from its 90-litre diesel tank.
It’s supremely comfortable and very quiet, wth that customary cocoon-like enclosed sensation that you only ever truly get in a vehicle this far away from cheap.
The 450d is 5080mm long, 1980mm wide and 1865mm high. It has a 11.8m turning circle. It has an official kerb weight listed as between 2510kg and 2740kg.
For something with so many kegs onboard, it’s capable of punching off the mark with a respectable bit of pace; handy for city-street bursts to slip through traffic gaps.
It never feels cumbersome; it actually feels quite light on its toes. In fact this Lexus tends to be more than a little bit floaty at times. You can select different suspension settings – comfort, normal or sport – to suit your preference.
Visibility is generous all-round with clear sightlines in all directions; besides, the reversing monitor with 360-degree view helps if your views are hindered.
Steering is generally active but it does exhibit quite a lot of under-steer on twisting country roads. It has paddle-shifters if you’re that inclined.
The LX 450d rides on 20-inch alloys and 20-inch Dunlop Grandtrak PT2As (285/50F20 112V) – a combination which is fine for bitumen-based outings, but we’d ditch it for rubber with more sidewall to allow for greater freedom to adjust tyre pressures to suit rough terrain.
It’s an enjoyable vehicle to drive, with multiple power adjustments for the seat and steering wheel combined with a large left footrest which provide supreme driver comfort and support.
The powerful and responsive turbocharged six-cylinder diesel and nine-speed auto are well suited to this application. The engine’s ample torque provides spirited acceleration from standing starts, taking only six seconds to reach triple-digit speeds.
This drivetrain would be well suited to heavy towing duties, given the 48V mild-hybrid system can contribute an extra 200Nm (in addition to the engine’s 750Nm), which raises the total theoretical torque output to almost 1000Nm.
The active air suspension provides a wonderfully cushioned ride that floats over bumpy roads, while maintaining excellent handling response and surprising agility. These commendable chassis dynamics, combined with the powerful and responsive drivetrain, makes the vehicle feel smaller and lighter than its dimensions and kerb weight would suggest.
Overall, it’s difficult to fault from a driver’s perspective, with the only exception being the voice activation function. This is often triggered by words or phrases other than ‘Hey Mercedes’ resulting in regular interruption of conversations. This needs some fine tuning.
The LX 450d has a five-star ANCAP rating. It has the latest-generation Lexus pre-collision safety system with pedestrian detection, and 10 airbags. Other standard safety gear includes radar active cruise control, lane-departure warning, adaptive high-beam system, blind-spot monitor and rear cross-traffic alert, as well as clearance and back sonar, and reversing monitor with 360-degree view.
The GLS does not have an ANCAP rating as it’s yet to be tested, but comes standard with a suite of passive and active safety features including nine airbags, auto emergency braking (AEB) with pedestrian detection and junction assist, blind-spot monitoring, traffic sign recognition, head-up display, rear cross-traffic alert, lane-keeping, adaptive cruise control with ‘distance assist’ (autonomously brakes/accelerates in heavy traffic), front/rear parking sensors, 360-degree camera and more.
There’s also two ISOFIX and three top-tether child seat anchorages in the second row, plus two more of each in the third.
Warranty is 4 yrs/100,000km. Service intervals with indicative pricing (exc GST) are: six months/10,000km: complimentary; 12 months/20,000km: $535.56; 18 months/30,000km: $598.11; 24 months/40,000km: $800.32; 30 months/50,000km: $502.44; 36 months/60,000km: $676.23.
The GLS comes with a five-years/unlimited km warranty (better than BMW and Lexus) and five years of roadside assistance. Scheduled servicing is every 12 months/25,000km whichever occurs first.
Mercedes-Benz offers capped-price pre-paid servicing packages with three, four or five-year terms. For example, the total upfront cost of the minimum three-year term is $4090, or an average of $1363 per service.