Mercedes-Benz Gls450 vs Renault Koleos

What's the difference?

The new GLS is everything you’d expect of a Mercedes-Benz with an S in its name. Luxury, performance, space, and in this case, thoughtful practicality. A super-capable, super-sized family truckster with the lot.

To be fair to Renault, when the second-generation Koleos launched in 2016, it was a competitive offering. The problem is, a bunch of medium SUV rivals have been replaced in that time and some of them - Toyota RAV4, Kia Sportage, Mazda CX-5 and Hyundai Tucson, to name a few - are high-quality offerings with an engaging drive and the latest tech and in-car features.

Unfortunately, that leaves the Koleos towards the rear of the medium SUV pack.

It offers solid value-for-money, handles reasonably well and is still one the best-looking SUVs on the road. But beyond that, the Koleos can’t keep pace with those top-notch rivals.

Launched globally in mid-2019, Merc describes the GLS as the S-Class of SUVs, which is apt given its 5.2m length, 2.5-tonne mass, and ultra-premium specification.

As mentioned, the GLS is big; a step up from the already substantial model it replaces. Built with the US market in mind, in fact it’s produced in Tuscaloosa, Alabama, it’s more than five metres long, close to two metres wide, and over 1.8m tall. And there’s more than three metres between the axles, a 60mm wheelbase increase over the previous model.

And despite the size of the canvas, the Benz design team has managed to make the GLS look like a modern Merc. Signature elements include obvious ones like the slatted grille with a couple of three-pointed stars on the nose.

But there’s also, the carefully chiselled twin ‘power dome’ bonnet, scowling LED headlights and vents to aid front brake cooling and smooth aero performance around the front of the car.

The big beast’s off-road intent is highlighted by extensions around the wheelarches, with big optional 22-inch rims sitting underneath. The fact they look right-sized for the car speaks volumes about its scale.

The racy AMG Line package is standard, and a recess and pronounced character line, tightening the lower waistline is a familiar Merc treatment, plus alloy roof rails toughen the look while dialling up practicality.

The rear is relatively simple, borderline generic, with tapered tail-lights offering the only strong whiff of design personality. But believe it or not, thanks to careful detail sculpting of the body, and smoothing underneath the car it boasts a drag figure of Cd 0.32. Outstanding aero performance for a large SUV.

The driver and front passenger are presented with a sweeping dashboard dominated by twin 12.3-inch digital screens, one primarily covering the instruments, and the central screen managing the MBUX media system, including audio, nav, phone integration, car set-up, and more, plus ‘Hey Mercedes’ voice control.

The overall feel is simple, and restrained, yet massively confident, with a subtle colour palette, large squared-off elements defined by brushed metal finishes, and an obvious, intense attention to detail, from the haptic controls to the beautifully finished, multi-function steering wheel.

And the standard Burmester audio system includes a two-way in-car communication function that subtly amplifies the driver and front passenger’s voices for those in the third row, and vice versa. Sheer genius.

An area that Renault has excelled at in the past decade has been exterior design. Under the stewardship of design chief Laurens van den Acker, Renault has transformed from somewhat quirky to modern and sleek.

The Koleos is getting on in years, having arrived in 2016, but it’s still a handsome SUV. A 2020 facelift sharpened its looks further and we reckon it’s one of the best-looking models in the medium-SUV segment.

Piano black inserts around the gear shifter are a nice touch, but the fake carbon-fibre inserts look and feel cheap. It’s all a bit generic.

But the appealing contrast yellow stitching on the seats, gear shifter housing, doors, centre armrest and more breaks up the grey with a little pop of colour.

Space is obviously a critical factor here, and no surprise there’s copious amounts of it inside the GLS.

Front seat passengers enjoy plenty of breathing room, without feeling remote from one another, and there’s lots of storage in the shape of a large lidded box/armrest between the seats, a decent glove box, two big cupholders and jumbo door pockets with room for large bottles.

There’s one data-enabled USB port in the front, two charge-ports in the second row, and four in the third row. Shouldn’t be any complaints about powering mobiles, tablets or games.

The second row feels every millimetre the SUV limo. Simply getting in and out is made easier because an auto lowering function drops the car 25mm when one of the doors is opened.

I was able to sit behind the driver’s seat set for my 183cm position with heaps of head and legroom on offer. And there’s an extra 10cm of electrically adjustable travel to play with if those in the third row agree.

The fold-down centre armrest features a lidded storage tray and twin pop-out cupholders. There are netted pockets on the front seatbacks, and again, the door bins are big enough for large drink bottles.

Three adults across the rear is a breeze, there’s climate control ventilation, and a huge glass sunroof is standard. Rather than asking ‘Are we there yet?’ the kids will be disappointed when you arrive!

Then there’s what the Cleary family refers to as ‘the way back seat.’ A pair of third row seats for the lucky kids that get to inhabit their own little world. Getting in and out is relatively civilised thanks to electric slide and tilt for the second row seats, and space is generous. I could sit comfortably, so the kids will be all smiles.

With all seats upright cargo capacity is enough for a seven-person day trip (355L VDA). Press the button to fold the 50/50 split-fold third row down and your options expand substantially (890L). And with 40/20/40 split-folding second row lowered, transportation of a full, three-ring circus is on the cards (2400L). Overall, more space than the arch enemy BMW X7.

Plus, the ability to lower the car 50mm thanks to the standard air suspension makes life even easier. And one button lowers the second and third rows at the same time.

The spare is a collapsible space-saver, and towing capacity for a braked trailer is 3500kg, with a tow ball weight of up to 140kg. The ESP system also features a trailer stabilisation function that counters oscillation with “braking intervention.”

It might lack the up-to-date styling of those rivals, but the Koleos is practical and spacious inside and great for family duties.

As with the outgoing fourth-generation Nissan X-Trail, the Koleos is one of the larger offerings in the medium SUV segment, and it’s evident when sitting in the front or rear seating row.

Rearward visibility could be better, with a small rear screen and thick C- and D-pillars impeding vision and creating a blind spot.

The front seats are well supported and comfortable and while the driver’s side is power adjustable, the front passenger seat is manually adjustable.

It has a deep central storage bin with a hidden shelf for coins and more. The Koleos features a sizeable glovebox and good bottle storage in the doors, with room for other items.

There’s a weird fixed cup holder in the centre console. It’s not adjustable and there’s room for two very narrow cups and two larger, but not wide, cups. It’s strange. Interior designers could have used that space better.

The CVT's position indicators are located to the left of the shifter and are thus obscured, so you have to rely on the instrument cluster display to confirm what gear you want. 

The steering wheel looks and feels good, but the controls aren’t super logical. There are old school switches in the console to activate the cruise control and speed limiter, but then to adjust and reset the speed you have to hit buttons on the wheel that are not clearly marked. 

The audio controls are housed on a panel-like stalk to the right side of the steering column, which isn’t ideal. These make more sense if they’re housed on the wheel itself. 

Along with a number of cars we have sampled recently, the Koleos has split analogue and digital controls for the air conditioning. Just integrate it in the screen or have traditional controls - not both!

It has a part-digital instrument cluster which is fine, but there’s no head-up display.

Renault’s 'R-Link' multimedia set-up in the Koleos is old, with dated graphics and a small screen, but the menu layout is clear and logical. 

The Koleos lacks wireless phone charging and it makes do with wired Apple CarPlay and Android Auto. The quality of the Bluetooth and CarPlay phone audio is poor and sounds tinny. 

The proximity key that locks and unlocks the vehicle remotely when you walk towards or away from it works every single time. Many of these systems from other brands are patchy at best but the Renault system is faultless. 

The rear seats recline and fold manually 60/40. They’re also surprisingly comfortable. There’s enough bucketing to sink in a bit, and the seats are set high up so kids can easily see out windows.

Space is ample in the second row, with loads of head, leg, toe and knee room, even behind my six-foot (183cm) driving position.

The rear pew has ISOFIX points on the outboard seats, lower air vents, a 12-volt outlet, map pockets, a centre folding armrest with two cupholders, but no USB ports. You have to make do with the two ports at the front.

Open the power tailgate and you’ll find a decent 458-litre boot with all seats in place (maximum 1690L), which is off the pace of its cousin, the Nissan X-Trail (565L), as well as the Toyota RAV4 (580L) and Hyundai Tucson (539L).

A 17-inch steel spare wheel is housed under the boot floor which might explain the lower boot capacity, and there are handy tie-down hooks, a couple of smaller storage nooks and a solid cargo blind. 

A European badge doesn’t always mean you pay more than say, Korean or Japanese offerings, and Renault is an example of that.

The Koleos line-up, for now, starts from $33,590, before on-road costs, for the two-wheel drive Life and tops out at $46,390 for the Intens all-wheel drive.

But after July 1, 2022, prices will increase across the Renault line-up, with the Koleos set to range from $35,000 to $47,500.

There’s only one petrol engine option since the diesel was dropped in 2019 and each variant is paired with a continuously variable transmission (CVT) driving either the front or all four wheels.

That pre-July pricing is competitive against its rivals, undercutting the opening price of automatic versions of the Hyundai Tucson, Kia Sportage, Mazda CX-5, Mitsubishi Outlander, Subaru Forester, Toyota RAV4, and more.

Our test car, the Koleos Black Edition, is priced at $40,090 (rising to $40,500 from July 1) and is based on the specification of the mid-range Zen front-wheel drive (FWD). It is limited to 400 units in Australia.

Renault is one of a number of car makers to offer a black-themed model in recent times, alongside Kia, Mitsubishi, Toyota, SsangYong, and others.

The Black Edition adds dark flourishes like 19-inch dark-grey alloy wheels, gloss black roof rails and door mirrors, sidesteps, French flags on the B-pillar (even though it’s built in South Korea) and a choice of three exterior metallic paint colours including black (of course), grey or white. 

It also gets a hands-free powered tailgate, black synthetic leather upholstery with yellow stitching, matt carbon-look inserts, an 8.7-inch multimedia portrait touchscreen and ‘Limited’ badging on the chrome door sills.

That’s on top of features that are standard on the Zen, like a proximity key, push-button start, dusk-sensing headlights, rain-sensing wipers, auto-dimming rear-view mirror, auto-folding exterior mirrors, an electrically adjustable driver’s seat, heated front seats, a reclining rear seat, dual-zone air-conditioning, and heated and cooled front cupholder.

The multimedia system houses sat nav and comes with wired Apple CarPlay and Android Auto, Bluetooth, digital radio and an eight-speaker audio system.

There’s more details on the safety front below, and many rivals come with more modern in-car tech but there’s no question the Koleos offers very good value-for-money. 

There are two engines on offer. The 3.0-litre (M256) in-line six-cylinder turbo-petrol GLS 450 4Matic, and the 2.9-litre (OM656) in-line six-cylinder turbo-diesel GLS 400 d 4Matic.

The all-alloy, twin-scroll single-turbo petrol engine delivers peak power of 270kW from 5500-6100rpm, and maximum torque of 500Nm across a broad plateau from 1600-4500rpm. It also features a 48-volt electrical system driving the ‘EQ Boost’ set-up, able to deliver an extra 16kW/250Nm for short periods. The integrated starter-generator also enables energy recuperation.

Although the all-alloy, twin-turbo diesel features variable valve lift it gives some ground on power, offering up 243kW between 3600-4000rpm, but torque is a solid whack, with 700Nm on tap from 1200-3000rpm. Worth noting, that to minimise emissions this engine features a “selective catalytic reduction converter” in the exhaust, which brings with it the use of an ‘AdBlue’ reducing agent. The separate AdBlue tank has a capacity of 31.6 litres.

The nine-speed auto transmission is the same in both versions, although the diesel has a slightly lower final drive ratio.

The Koleos shares its powertrain with the X-Trail. That means it uses a Euro 5-rated 2.5-litre four-cylinder, naturally aspirated petrol engine delivering 126kW of power at 6000rpm and 226Nm of torque at 4400rpm.  

It is paired with a CVT and drives with the front, or all four wheels, depending on the grade. 

The Koleos has a braked towing capacity of 2000kg.

Claimed fuel economy for the combined (ADR 81/02 - urban, extra-urban) cycle for the GLS 450 is 9.2L/100km, the more frugal GLS 400 d trimming that to 7.7L/100km. The petrol 450 emits 210g/km of CO2 in the process, the diesel 400d dropping that slightly to 202g/km.

Stop-start is standard, you’re looking at premium unleaded for the 450 GLS, and you’ll need 90 litres of dinosaur juice to full the tank on both models.

According to Renault, the combined fuel consumption figure for the FWD Koleos is 8.1 litres per 100 kilometres. The AWD Koleos sips 8.3L.

After a week of mixed urban, freeway and semi-rural driving, we recorded 11.3L/100km.

Koleos uses 91 RON petrol, has a 60-litre fuel tank and emits 188g/km of CO2 emissions.

Merc claims the GLS 450 will sprint from 0-100km/h in 6.2sec, and the 400 d in 6.3sec. Not hanging around for a 2.5 tonne mothership. But the standout is the 400 d’s torque. All 700Nm of it available from just 1200rpm to 3000rpm; right in the mid-range sweet spot.

The nine-speed auto transmission is smooth yet responsive, with paddles on the wheel for manual shifts when you want to pick the ratio. The combination of effortless grunt and the nine-speeder keeping things on the boil is an impressive one.

Suspension is by double wishbones at the front and multi-links at the rear, and while you can feel the weight in cornering, the standard Airmatic air suspension (which does away with steel springs) is superb in terms of ride comfort and body control.

We took a deep breath and pushed enthusiastically through a series of sweeping corners and the fat (285/45 fr - 325/40 rr) Continental ‘PremiumContact 6’ rubber wrapped around our car’s (optional) 22-inch rims gripped hard.

The ‘4Matic’ all-wheel drive system also seamlessly shuffles torque between the front and rear axles (theoretically up to 100 per cent in each direction).

Merc has put extra focus on body rigidity, the tuning of engine and suspension mounts, and sound absorption, and it shows. The GLS 400 d is beautifully refined on the highway. A neat touch is the car automatically lowering 15mm at motorway speeds or when ‘Sport’ mode is selected.

Steering is electromechanically assisted, and Merc says the front suspension geometry has been revised to minimise vibration through the wheel. And yes, feedback is minimal, but unfortunately so is road feel with only a general connection between your hands on the wheel and the front tyres on the bitumen.

When you’re steering a large beast like this, often with something substantial hitched to the back, you want to know braking performance is up to the task, and the GLS’s big ventilated discs all around deliver reassuringly strong stopping power, with nice, progressive pedal feel to boot.

The seats are adjustable six ways to Sunday, but beyond that they’re comfortable and supportive, even over long stints behind the wheel.

We stayed on the bitumen, because, let’s face it, that’s where this car will spend 99.9 per cent of its time, with the exceptions of the boat ramp, a ski weekend or pony club.

For those special occasions the optional ‘Off-road engineering package’ adds a low-range transfer case, inter-axle locking, hill descent control, and under body armour for more serious work.

The drive experience is a mixed bag with some highlights and lowlights.

The ageing 2.5-litre engine is responsive enough from a standing start - it has a 0-100km/h time of 9.5 seconds - but it lacks any real punch and becomes breathless the second you encounter a hill.

It is noisy and revs hard when pushed, with the CVT drone not making for a particularly pleasant aural experience. You’ll hear a fair bit of road and tyre noise in the cabin, too.

The steering is dull and feels quite artificial, but the brakes feel strong.

Unless you’re on a perfectly smooth road surface, the ride is a little busy and the damper tune fails to adequately soften corrugations, potholes and speed bumps. 

It is, however, a more capable handler than expected. The chassis is well sorted, and aside from feeling top heavy with body roll when cornering, it has decent grip and displayed impressive roadholding characteristics, even on a sweeping bend with a loose shoulder surface.

There was a little understeer detected turning into a particularly tight bend.

It can’t match the dynamism of the Kia Sportage or Mazda CX-5, but it does engage the driver to some extent.

The Koleos was awarded a five-star ANCAP crash safety rating back in 2017.

It comes as standard with six airbags, auto emergency braking, forward collision warning, lane departure warning, blind spot monitoring, cruise control, a reversing camera, front and rear parking sensors, and a tyre pressure monitor. 

It lacks some of the more modern active driver aids that are offered as standard in rivals, like an active lane-keeping system that helps ensure the vehicle doesn’t cross line markings. The Koleos makes do with an audible warning that, oddly, sounds like a whoopie cushion when activated.

The cruise control is not adaptive, instead it’s the old school version that doesn’t detect vehicles ahead and lower its speed accordingly. 

Having more up-to-date safety gear would improve the Koleos’ appeal.

The Mercedes-Benz range is covered by a three year/unlimited km warranty, which, like Audi and BMW continues to lag behind the mainstream market where the majority of players are now at five years/unlimited km, with some at seven years.

On the upside, Mercedes-Benz ‘Road Care’ roadside assistance is included in the deal for three years.

Service is scheduled for 12 months/25,000km (whichever comes first) with pricing available on an 'Up-front' or 'Pay-as-you-go' basis.

As a guide, service pricing for the outgoing GLS is set at $2600 per service (up-front) and $3250 (PAYG), a saving of $650 a pop. Fourth and fifth services are also available for pre-purchase ($3550 and $4900).

The Koleos is covered by Renault’s five-year/unlimited kilometre warranty, which is stadatd in the meainstream market, now. 

It is available with a five-year capped-price servicing plan, with each service costing $429, except year four which will set you back $999.

The servicing schedule is every 12 months or 30,000km, whichever occurs first.