From £52,8807

Sales star of the Mercedes range is re-engineered to stay fighting fit

When the Mercedes GLC first arrived in 2016, we joked that the executive who decreed that its predecessor (badged 'GLK') would not be offered in the UK would be lucky to have remained in the job.

Even back then, when the Audi Q5BMW X3 and Land Rover Discovery Sport were already flying out of showrooms, it felt like quite an oversight not to offer the GLK in right-hand drive. In the seven years since, during which time the GLC has become Mercedes’ best-selling model, it seems even more confounding that the brand was so very late to the booming mid-size SUV party. 

However, Mercedes now seems keen to continue heartily making up for lost time. The second-generation GLC tested here was revealed last year and does very little to shake things up over its forebear. At a glance it can be difficult to tell the ‘X254’ GLC apart from the original, and the inherent message in that is clear: this is very much the same car to which buyers have taken so warmly, only updated and improved to better compete with new rivals. 

Under the skin is where the real changes lie. The model range is now hybrid-only, with mild- and plug-in hybrid powertrains. Developed alongside the new Mercedes C-Class saloon, the car also features rear-wheel steering, albeit as an optional extra, and is notably stiffer in its structure, which ought to improve dynamics. Inside, Mercedes claims to have used more desirable materials to further capitalise on the GLC’s reputation for relative opulence in this class. 

The range at a glance

Models Power From
220d 4Matic 194bhp £52,635
300 4Matic 255bhp £53,635
300d 4Matic 266bhp £61,175
300e 4Matic 308bhp £63,210
300de 4Matic 326bhp £65,460
AMG 43 415bhp tbc
AMG 63 S E Performance 671bhp tbc
Transmission 9-spd auto  

The GLC is well furnished with diesel options, which feels something of a novelty these days. Equally, when you boil it down, there’s not much variation: your choice is from four- cylinder diesel and petrol engines, either with a 48V mild-hybrid system or a full plug-in hybrid set-up. It’s a shame the straight-six 400d won’t be offered in the UK (for now), though upcoming AMG variants will add flavour to the range. Mercedes’ nine-speed automatic is standard across the range, as is one of three grades of AMG Line specification.

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DESIGN & STYLING

mercedes glc review 2023 02 cornering rear

Most GLCs will be built at Mercedes’ plant in Bremen, Germany, alongside the C-Class saloon with which the model shares its second-generation, natively rear-driven MRA II (for Modular Rear Architecture) platform. The fact that this looks like a minor facelift is misleading: the chassis itself is 15% stiffer than before, supports a 48V electrical system and now underpins a car 60mm longer and 21mm narrower (yes, narrower) than previously. Around 15mm of the increase in length is accounted for in the wheelbase, which should benefit rear leg room – an area where the GLC was never especially strong against the competition. 

Seven engines will be available in the UK, ranging from a 2.0-litre turbo diesel in the entry-level 220d 4Matic through to mild-hybrid and plug-in hybrid petrol options. Eventually, these regular models will be joined by AMG specials in the form of the 415bhp GLC 43 and the 671bhp GLC 63 S E Performance plug-in hybrid. The big news for the AMG derivatives is that no longer will you find a high-capacity V8 or even a V6 in the noses of these cars. Instead, a version of the M139 2.0-litre four-cylinder unit that made its debut in the A45 will feature, and with considerable electric motor assistance in the 170mph GLC 63 S. Anybody craving a decent cylinder count will need to wait and see if Mercedes brings the GLC 400d to the UK, which would use the brand’s fantastically smooth straight-six turbo diesel.The car’s suspension varies depending on engine. The plug-in hybrid 300e will use self-levelling air suspension for the rear axle, while all other non-AMG GLC models have conventional steel springs all round. Rear-axle steering, which reduces the turning circle from 11.8m to 10.9m thanks to 4.5deg of rotation, is also only available on the PHEV, which benefits from some 80 miles of claimed electric range thanks to its enormous 31.2kWh battery. 

Don’t discount the petrol PHEV. This powertrain in the C-Class, which delivers around 55 miles of real- world EV range, is pretty compelling if your routine suits it. The bigger- battery GLC may even manage a bit more range.

For entirely steel-sprung cars, Mercedes is only offering its ‘sport’ springs in the UK. This is a knock-on effect from Mercedes only selling the GLC in varying shades of AMG Line specification over here. Interestingly, other markets, such as Australia, go the other way, taking only the ‘comfort’ spring. Another knock-on effect of AMG Line is a minimum wheel diameter of 19in, rather than the 18in that less sporty trim levels can be fitted with. GLCs that are not fully fledged AMG models also use passive dampers all-round.

Our test car is the mild-hybrid 255bhp GLC 300 in AMG Line Premium Plus trim. Like every GLC, it also has two driven axles, with a permanent torque split that marginally favours the rear. Torque is syphoned off from the nine-speed automatic gearbox, through a transfer case, and to the front axle. This car also rides on 20in wheels – an inch larger than standard and the largest offered. On our scales, it weighed 1929kg, just 4kg more than the claimed figure and 36kg less than the non-hybrid, less generously specified GLC 250d 4Matic we road tested back in 2016. 

INTERIOR

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Mercedes has in recent years prioritised visual impact over deep-seated material quality and fit and finish. It’s fair to say this approach has been applied to the new GLC. 

The transmission tunnel flows seamlessly into the 11.9in infotainment touchscreen to breathtaking effect, and the ambience-lifting ‘anthracite linestructure lime wood’ finish of our test car’s cascading dashboard is lifted from the current S-Class. As, for that matter, is the steering wheel, whose slimmed multifunction spokes represent a vast improvement over the old car’s chunky interfaces. The driving environment is less cluttered with switchgear and more premium in feel than before, while hefty window sills and a comparatively high beltline give the GLC a feeling of protectiveness that those shopping in this class want. That said, the driving position is still decidedly car-like, the GLC never feeling intimidating.

So the GLC probably has more ‘wow’ factor than any rivals. But, equally, perceived quality is behind what you would find in the comparative BMW, Lexus or Audi. The problems here aren’t scratchy plastics or substantial panel gaps – the GLC isn’t that bad. It’s more that various surfaces flex more than they should; it’s in the imprecision of controls like those for the mirrors or those on the multifunction steering wheel, where different commands are grouped under the same plastic panel; and it’s in the unconvincing ‘metal structure’ finish found on the door cards and the high-set air vents. All this undermines the visuals a touch. 

In practical terms, the GLC wants for little. Occupant space is very good, front and rear, though anyone in the middle berth in the back will have to compete with a pronounced transmission tunnel. The car’s longer rear overhang also results in 70 litres more boot space than before, with a total of 620 litres bettering that offered by the Audi Q5 and BMW X3. 

Multimedia system

Mercedes glc review 2023 09 infotainment 0

The MBUX system inside the GLC is the same that was introduced in the current S-Class and feels commensurately plush, with deep colours and crisp graphics. It must be said, however, that the reclined nature of the 11.9in touchscreen display does mean that fingerprints catch the light to less than desirable effect. And because there is now no click wheel or such, your only other option to input commands is via the steering wheel controls, which isn’t especially intuitive. There’s a considerable degree of swiping involved, much of the time.

The central display does at least present you with clear climate controls that don’t require any digging through sub-menus to access. The smartphone integration is also good, and the positioning of the display keeps it in arm’s reach, which isn’t always the case with dash displays.

ENGINES & PERFORMANCE

mercedes glc review 2023 02 cornering rear

The GLC 300 pairs a mild-hybrid, 2.0-litre four-cylinder turbocharged engine with Mercedes’ nine-speed 9G-Tronic torque-converter automatic. Mild hybridisation owes to the fact that for this generation of GLC, in non-PHEV models the engine’s alternator is replaced by an integrated starter-generator unit, which can provide a boost of up to 23bhp at low engine speeds. Most of the car’s combined 255bhp and 295lb ft flows to the back axle, but longitudinally engined Mercedes fitted with 4Matic also permanently engage their front axles, in this case with 45% of available torque.

The GLC 300’s performance is far from what you would call exciting, but neither does this car feel in any way slow. A 0-60mph time of 6.5sec and the 6.0sec needed to cover 30-70mph through the gears are all that’s needed from an unobtrusive, premium family SUV, and this Mercedes motor delivers its efforts methodically, with peak torque coming on stream from just 2000rpm. Impatient owners who feel the need to overtake often, and with passengers and luggage aboard, may want to consider the GLC 43 when it arrives, but for most people a car that will crack 60mph in exactly the same time as what we recorded for the Volkswagen Mk7 Golf GTI back in 2013 will probably suffice. That the big Mercedes needs only 20cm more to stop from 70mph than its compatriot hot hatch deserves credit too. 

This gearbox is also perfectly able and for the most part shifts with slick precision. It can occasionally hiccup from first to second, and nine close-spaced ratios do sometimes seem to lack a clinical kickdown strategy, but it mostly goes unnoticed, which is as you would want it. Our only other criticism is that, under load, this is not the most quiet motor. It doesn’t sound unpleasant, but it’s hardly memorable and isn’t as well isolated as units from BMW or Audi.  

RIDE & HANDLING

mercedes glc review 2023 04 panning

Because it is based on an adapted C-Class platform, you would expect the GLC to possess an underlying feeling of poise and pedigree. Nobody is expecting Porsche Macan levels of engagement here, but maturity and an easy-going composure are must-haves for this particular brand, at this price point.

As it happens, the GLC does have an underlying handling flair (see Track Notes, right), but on the road its priorities are more prosaic, if no less worthy. This SUV changes direction with the neat, controlled surety of a traditional saloon, and the fact that the driving position is relatively low plays into the GLC’s notably car-like handling. Yes, in terms of feel and feedback the steering cuts a slightly disinterested figure, but it’s accurate, well geared and mostly intuitive. The motion itself seems to possess a certain thinness and it must be said that the helm of a BMW X3 is considerably more rich in its action and feel, but such concerns are unlikely to trouble the majority of owners.

My ideal spec of GLC would be one we won’t be getting in the UK: a 400d, on 19in wheels, possibly with the Siena brown and black interior. Such a car would be on the expensive side but it could also potentially be truly magnificent daily company.

Push on and the GLC 300 does begin to feel discernibly natively rear-driven, but by and large it handles with rock-steady neutrality. This allows it to cover ground very effectively and easily indeed. Note also that, in the UK, all models apart from the plug-in hybrid 300e will ride on Mercedes’ ‘sport’ springs, which engender plenty of composure and help the GLC to consistently get the available power down. While it breaks no ground in dynamic terms, this is a suitably quick SUV that prizes security, which is just what’s required.

Comfort & Isolation

When the original GLC arrived in 2016, we criticised its AMG Line suspension for its brittleness on poorer surfaces. Seven years later, we have similar complaints – albeit lesser in severity. While the new GLC has a fine primary gait, the steel coils of its AMG Line suspension (which are undoubtedly not helped by our test car’s 20in wheels) still struggle to isolate you on rougher roads and some unwelcome sensations travel up the steering column.

This brittleness seems to be a classic case of setting a car up for German roads, with little thought to how it might fare in the UK. None of this is massively pronounced, but it is noticeable, so while Mercedes should be leading the field when it comes to refinement, in this case the product is mostly fine but isn’t notably, if at all, superior to the BMW X3 et al. Tellingly, a C-Class on 19in wheels out-rides a GLC on 20in wheels in almost all cases.

In terms of outright isolation, the GLC isn’t perhaps quite as strong as you might expect from Mercedes, either. The engine is docile at idle, but at a 70mph cruise the GLC 300 (69dBA) couldn’t beat even the BMW X1 xDrive23i (67dBA) – on M Sport suspension, no less – that we tested earlier this year. 

MPG & RUNNING COSTS

mercedes glc review 2023 01 cornering front

Unsurprisingly, a new generation has brought with it price rises. Where the outgoing GLC could be had for less than £45,000 in entry-level 220d form, the equivalent model now costs a shade under £53,000. Of course, the mild-hybridisation of the powertrain hasn’t come cost-free to Mercedes, and component costs have risen across the board. But this is a more expensive car than ever, and costs more to buy outright than alternatives from BMW, Audi and Lexus, so owners will feel inclined to expect improvements in certain areas.

One of those areas is standard equipment, and the GLC is generously kitted out across the board, though to get the panoramic roof that really lifts the cabin atmosphere, or the 13-speaker Burmester sound system, you need the top-rung AMG Line Premium Plus. In terms of the digital array, the only reasons to go higher than base trim are if you want a head-up display and augmented reality for the navigation.

Consider the entry-level, AMG Line model. It will be the best-riding car in the line-up and comes well equipped, with the full MBUX infotainment array. It’s just a shame you can’t option one of the more colourful interiors with it.

In terms of efficiency, our GLC 300 test car returned a touring economy of 41.2mpg, which with the 62-litre tank translates to a range of 561 miles. Judicious use of the throttle, combined with the gentle 23bhp boost from the mild-hybrid system, would allow you to see the mid- to high-30s in everyday driving.

VERDICT

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When it comes to its mid-size SUV, Mercedes knows what today’s customers want, which is slick exterior design, an unobtrusive driving experience and an interior capable of impressing, and not just because of an array of vivid digital displays.

In these respects, the new GLC hits all its marks. It’s not hard to see why a potential buyer might find the BMW X3 a little ordinary and the Audi Q5 a touch joyless. This Mercedes has an outward appeal, and mild-hybridisation has also improved matters. In the case of the 300, this has boosted combined fuel economy by around 15%, with benefits that also translate into real-world driving.

It is in the fundamental matters of outright ride quality and dynamic character that the GLC fails to put on a memorable show. As its best-seller, for Mercedes this car presents a chance to really blow the competition away in terms of refinement and underline its core brand value, yet the GLC’s road manners aren’t free of flaws. Neither does the car’s dynamic persona impart much sense of mechanical integrity. It remains broadly desirable enough to sell well, and is more practical than ever, but doesn’t sparkle.

Richard Lane

Richard Lane
Title: Deputy road test editor

Richard joined Autocar in 2017, arriving from Evo magazine, and is typically found either behind a keyboard or steering wheel.

As deputy road test editor he delivers in-depth road tests, performance benchmarking and supercar lap-times, plus feature-length comparison stories between rival cars. He can also be found on Autocar's YouTube channel

Mostly interested in how cars feel on the road – the sensations and emotions they can evoke – Richard drives around 150 newly launched makes and models every year, and focuses mainly on the more driver-orientated products, as is tradition at Autocar. His job is then to put the reader firmly in the driver's seat. 

Away from work, but remaining on the subject of cars, Richard owns an eight-valve Integrale, loves watching sportscar racing, and holds a post-grad in transport engineering. 

Mercedes-Benz GLC First drives