Mercedes-Benz CLA45 vs Audi A8

What's the difference?

The new CLA 45 S has knockout performance to match its knockout looks, neither of which are much of a surprise given the ingredients involved.

That said, it is far from perfect, with questions raised over its value and practicality. And for those reasons, we’d be buying the A 45 S hatch instead.

Is the new CLA 45 S worth such a hefty premium over its non-S predecessor? Tell us what you think in the comments below.

The Audi A8 swims in a luxury car shark tank where those paying the big dollars expect top-shelf everything. It delivers a serene driving experience whether you’re in the front or the back, in a superbly engineered and executed luxury sedan package. Not perfect, but very, very impressive.

There’s simply no mistaking the CLA 45 S from its CLA siblings. It’s angry and stylish, at the same time.

Up front, Mercedes-AMG’s signature 'Panamericana' grille insert is large and in charge, flanked by adaptive 'Multibeam' LED headlights that incorporate sinister-looking daytime running lights (DRLs).

The real action, however, is happening below, where the AMG body kit starts to come into frame. It’s delightfully chunky and highlighted by cavernous side air intakes, which hint at the sledgehammer residing beneath a bonnet featuring prominent power domes.

Around the side, the CLA 45 S does its best impersonation of a coupe, with a sloping roof line and a curvaceous glasshouse. It also brings the aggro with a particularly sporty set of 19-inch alloy wheels, which flank pointy side skirts.

At the rear, the CLA 45 S again hints at its performance level, this time with a bootlid lip spoiler, although look past its LED tail-lights and you’ll find the star of the show, a furious diffuser that houses the quad 90mm tailpipes of the AMG sports exhaust system.

Inside, the CLA 45 S is pretty special. While the CLA certainly provides the building blocks, it goes a step further with a number of unique touches.

Your eyes are immediately drawn to the wickedly cool 'Dinamica'-trimmed AMG Performance steering wheel, which not only has paddle-shifters, but also features two ‘display buttons’ that make adjusting vehicle settings on the fly super easy.

Then there are the front sports seats, which are covered in Lugano leather upholstery alongside the armrest door inserts, while artificial cow hide trims the upper dashboard and door shoulders.

Hard plastics? You’ll need to look lower than the soft-touch middle dashboard to find them, as they are primarily confined to the lower sections of the cabin. And yes, some of the switchgear is very cheap for a six-figure performance car.

One personal bugbear, though, is the liberal use of gloss-black trim for the centre stack and console. Not only is it a fingerprint magnet, but it scratches easily, too. The brushed stainless-steel and silver accents elsewhere are nice, though.

While stainless-steel sports pedals also help to make the CLA 45 S stand out from the CLA crowd, it is otherwise a carbon-copy of its siblings, which is no bad thing.

Of course, the headline act is the pair of 10.25-inch displays, with one a touchscreen that is partially concealed by the steering wheel, while the other is a digital instrument cluster.

The former delivers the now-familiar 'MBUX' multimedia system, which is still at the cutting edge when it comes to functionality, especially with its always-on natural voice recognition, which is as good as it gets, albeit not perfect.

There are, of course, more input methods, with two small touchpads located on the steering wheel, while a larger item sits on top of the centre console, supported by a palm rest. There are also shortcut buttons and physical climate controls.

The A8 is close to 5.2 metres long, yet instantly recognisable as an Audi thanks mainly to its evenly weighted proportions, gently curved roofline and overall high-waisted design. Worth noting its drag coefficient (Cd) is an impressively slippery 0.25.

The characteristic look is accentuated by the brand’s signature, six-sided grille, in this instance highlighted by a matrix of high-relief chrome accents. And typically angular LED Matrix headlights sit either side.

Check out our video review for the carefully orchestrated animation they run through when the car is unlocked.

The car looks equally svelte and contemporary from the rear, with just the right amount of chrome lifting the tone and multi-spoke 20-inch rims filling the wheel arches nicely.

As you’d expect, the top-shelf look and feel continues inside with the seats trimmed in aniline leather, perforated on the front and outer rear positions, with genuine hide also covering the centre console, door rails and armrests, steering wheel and upper dashboard.

Fine grain ash wood inserts sit alongside brushed metal elements and a meticulous attention to detail is obvious… everywhere.

For example, the interior door handle design has been thoroughly thought through, requiring a simple underhand tap to open the door, rather than the more conventional, and ergonomically convoluted, ‘over the top’ movement.

Three sleek screens dial up the tech - a 10.1-inch multimedia interface at the top of the centre stack, an 8.6-inch display below it for heating and ventilation, and a 12.3-inch version of Audi’s ‘Virtual Cockpit’ in the instrument binnacle.

And the spacious rear is the epitome of cool, calm Teutonic form and function. You feel relaxed the moment you get in, and isn’t that the primary aim of a car like this?

Measuring 4693mm long, 1857mm wide and 1413mm tall, the CLA45 S is actually similar in size to a C-Class but not quite as practical.

Cargo capacity is pretty good, at 460L, but can be increased via the 40/20/40 split-fold three-seat rear bench stowed – an action that can be performed via the boot’s manual release latches, although it doesn’t tumble forward by its lonesome.

Speaking of the boot, four tie-down points are on hand for to help loose loads alongside two side storage nets. Bulkier items will have to contend with a tall load lip. That said, the boot’s aperture is much wider than before, which is good news.

In-cabin storage options are okay, with the glove box decently sized and the map pockets of the net variety, while the central bin is fairly average, although it does house two USB-C ports.

There’s also a standard sunglasses holder and a cubby in front of the centre console’s two cupholders. It isn’t that useful, though, as the wireless smartphone charger takes up most of space alongside a USB-C port and a 12V power outlet.

The front door bins can accommodate two regular bottles each, while their counterparts in the rear take only one apiece. That said, the second row does have a fold-down armrest with another pair of (flimsy) cupholders.

Rear occupants don’t have a whole lot of room to play with, though. Legroom behind my 184cm driving position is pretty decent, at around four centmetres, but headroom is not. In fact, it’s non-existent sitting upright, with the panoramic sunroof not helping matters.

Toe-room is also at a premium alongside precious footwell space, which is reduced by the tall transmission tunnel. As such, the second row is best for up to two adults or three children at a time.

And if there are three occupants abreast, they’ll have to compete for the two USB-C ports, which are located in a fold-out cubby below the central air vents at the rear of the centre console.

For reference, child seats can be fitted in the second row thanks to top-tether and ISOFIX anchorage points, although both are only available for the outboard seats.

Space is luxury, be it a large house, a first class seat or a spacious car, and at nearly 5.2 metres long with a close to 3.0m wheelbase the Audi A8 measures up. 

Even before you get in, the doors have an amazing sense of solidity and quality. It’s like opening and closing a bank vault… if that huge circular door had a power-assisted soft-close function. 

There’s copious amounts of space for the driver and front passenger with lots of storage including a lidded box between the front seats, complete with a two-piece longitudinally split top design, so you can sneak your half’s open without displacing your neighbour’s elbow.

The door bins are decent but there isn’t a specific cut-out for bottles, so it’s more a case of laying them down than standing them up. There’s also a handy covered cubby at the end of the door armrests.   

The glove box is a good size and there are two cupholders under a pop-up cover in the centre console.

Of course, the back is where space really counts, and there’s as much room as you’d find in, well… a limo.

Sitting behind the driver’s seat, set for my 183cm position, I enjoyed copious amounts of head, shoulder and legroom. 

There are electric sunblinds for the rear and rear side windows, controlled by buttons in the door as well as the rear seat remote, a 5.7 inch OLED display housed in the beautifully trimmed fold-down centre armrest (which also has a soft close function!). The remote also allows adjustment of the lighting and climate control. Classy.

There’s a shallow storage box and twin cupholders in the armrest, medium size door bins and hard shell pockets on the front seat backs. The rear armrests also feature a small lidded cubby. 

In terms of connectivity and power options there’s wireless Android Auto and Apple CarPlay, a USB-A and USB-C in the front, and an identical pair in the rear, as well as a 12-volt socket in the front and two in the back.

Boot volume is a useful 505 litres (VDA) and the lid is electric, with gesture control. It’s able to easily swallow our three-piece luggage set or the bulky CarsGuide pram. And while the rear seats don’t fold there’s a ski port door to accommodate long items. Just make sure you use the tie-down anchors in the boot to ensure they’re properly secured. There’s a handy netted section behind the left wheel well and a cargo net is included.

Maximum towing capacity, for a braked trailer, is 2.3 tonnes (750kg unbraked) and in more good news, the spare is a space-saver rather than the increasingly prevalent inflator/repair kit.

With an entry price of $202,700, before on-road costs, the A8 is in the thick of it amongst its full-size primo sedan competitors from Europe and Japan. Specifically, BMW’s 740i MHEV ($272,900), the Lexus LS500h ($195,920), Maserati Quattroporte GT ($210,990), Mercedes-Benz S450 ($244,700) and Porsche’s Panamera ($207,800).

By definition, a luxury car should be loaded to the gunwales with features that make life on the road that little bit easier. And aside from the performance and safety tech we’ll cover shortly, the highlights from a very lengthy standard equipment list are - 20-inch alloy rims, metallic paint, adaptive cruise control, digital matrix LED headlights, digital OLED tail-lights, full keyless entry and start, power-assisted door closing, power boot lid (with gesture control), a panoramic sunroof, heated, ventilated and massaging electrically adjustable front seats, heated front armrests and extended leather trim (centre console, door rails and armrests, steering wheel and upper dashboard).

Also included are ambient interior lighting (with 30 colours and six colour profiles), four-zone climate control, electric sunblinds for the rear and rear side windows, ‘Audi Connect’ navigation and multimedia (with voice and handwriting recognition), wireless Android Auto and Apple CarPlay, 17-speaker 730-watt Bang & Olufsen audio (with digital radio) and a colour head-up display.

There’s a lot more, and the A8 can hold its head high in terms of pricing and features relative to its $200K price tag and the competition.

The CLA45 S is motivated by the most potent series-production four-cylinder engine yet.

The 2.0-litre turbo-petrol unit punches out an astounding 310kW of power at 6750rpm and a significant 500Nm of torque from 5000-5250rpm – a marked 30kW/25Nm improvement over its non-S predecessor.

It’s also worth noting Mercedes-AMG performed “torque shaping” to make the new engine’s output delivery (or curve) akin to that of a naturally aspirated unit. This attitude also led to a screaming redline of 7200rpm.

An eight-speed dual-clutch automatic transmission is responsible for swapping gears, while Mercedes-AMG’s fully variable '4Matic+' system sends drive to all four wheels, although it does have a 'Drift Mode' that effectively disengages the front axle.

With the help of standard launch control the CLA 45 S sprints from a standstill to 100km/h in four seconds flat, while its top speed is electronically limited to 270km/h.

The Audi A8 50TDI is powered by a 3.0-litre turbo-diesel V6 engine sending 210kW (from 3500-4000rpm) and 600Nm (from 1750-3250rpm) to all four wheels via an eight-speed automatic transmission (with ‘Tiptronic’ sequential manual shift function) and Audi’s quattro constant all-wheel drive system using a self-locking centre differential.

It also features a 48-volt electrical set-up for mild hybrid functionality built around a belt connected starter/generator, AC to DC converter and a 48-volt lithium-ion battery. 

With energy recovery of up to 12kW from regenerative braking, it enables the A8 to regularly coast with the engine switched off and helps the extended stop-start system to operate smoothly. 

Fuel consumption on the combined-cycle test (ADR 81/02) is 8.9 litres per 100 kilometres for the CLA 45 S, while its claimed carbon dioxide emissions are 202 grams per kilometre. Both are pretty keen given the level of performance on offer.

In our real-world testing, we averaged 12.0L/100km over 270km of driving evenly split between city traffic and highways. This result was somewhat inflated by some ‘spirited’ driving but is certainly something we can learn to accept.

For reference, the 51L fuel tank in the CLA 45 S takes 98 RON premium unleaded petrol at minimum.

Audi’s official fuel economy number for the combined (ADR 81/02 - urban, extra-urban) cycle is 6.6L/100km, the 3.0-litre turbo-diesel V6 emitting 175g/km of CO2 in the process.

Over a week of city, suburban, and some freeway running we averaged 11.1L/100km, which is acceptable for a 2.1-tonne luxury sedan.

Also worth noting the standard stop-start system works beautifully thanks to the 48-volt starter/generator.

You’ll need 82 litres of diesel to fill the tank and using the official number, that translates to a range of just over 1240km, which drops to around 740km using our real-world figure.

When it comes to sheer driving pleasure, the CLA 45 S is a huge step-up over its non-S predecessor.

Of course, the 2.0-litre turbo-petrol four-cylinder engine will steal all the headlines, and rightfully so; it’s the most potent unit in its class by some margin.

In reality, it absolutely slaps. Simply put, acceleration is addictive, and not just because of the outputs, but also the way in which they’re delivered.

The CLA 45 S does its best impression of natural aspiration, and I can’t help but award it an automotive Oscar.

Don’t get me wrong, performance is still strong down low (despite a hint of turbo lag), with it progressively building into, and through, a hard-hitting mid-range before reaching a knockout top end that you’ll want to revisit time and time again.

That said, it does take two to tango, and what a dancing partner the eight-speed dual-clutch automatic transmission is.

It’s almost flawless, with its gear changes stereotypically super quick but uncharacteristically buttery smooth at the same time.

Responsiveness is another strong point, although it does sometimes have difficulty recognising when the fun is over, as it can hold onto the short lower gears for a little longer than necessary.

And despite our initial fears, the CLA 45 S is still very, very vocal, with its sports exhaust system serving up plenty of aural pleasure, albeit not quite as much as the original CLA 45.

The soundtrack is booming and is complemented by plenty of pops on downshifts and the overrun as well as frightening crackles when aggressively up-shifting . But these theatrics require the Sport Plus drive mode to be engaged, which opens up an all-important exhaust valve.

Given the level of performance on offer, you’d be right to assume the CLA 45 S has a firm ride, but it’s actually better balanced than most.

The 'AMG Ride Control' sports suspension on hand consists of MacPherson-strut front and multi-link rear axles with three-stage adaptive dampers, which progressively stiffen things up.

However, all is relatively comfortable, even in the stiffest setting. In fact, only sharper edges are felt. It’s more than liveable, especially considering the benefits of the trade-off.

Speaking of which, the CLA 45 S loves to eat up corners. Handling is more or less neutral when pushing hard, at which point its 1687kg kerb weight starts to be felt.

Nonetheless, body control is very strong, partially thanks to the reinforced chassis, with only a hint of roll encountered when cornering with intent.

A lot of the credit has to go the fully variable 4Matic+ all-wheel drive system with rear torque vectoring, which provides outstanding grip, even in the poorest of conditions.

In fact, it bestows such confidence you'll want to push harder to try and find the limits of adhesion. A staggering effort.

The CLA 45 S isn’t without its flaws, though, with the electric power steering on tap good but not great.

It’s speed-sensitive and has a variable ratio, which mean it’s pleasingly light in hand at low speed and noticeably heavier at high velocity, with the latter exacerbated when playing with the available drive modes.

Either way, it’s nice and direct and provides a good amount of feedback through the wheel, but we feel Mercedes-AMG could’ve taken it even further in these two departments to really mix it up with genuine sports cars.

What isn’t half-baked, though, is the 'AMG High Performance braking system', which consists of 360 x 36mm front and 330 x 22mm ventilated discs with six-piston fixed and single-piston floating red callipers respectively.

This set-up washes away speed with ease, instilling the driver with even more confidence when tackling a winding road, while pedal feel is good. Yep, the CLA 45 S decelerates nearly as well as it accelerates.

Despite extensive use of aluminium in the ‘ASF’ platform and body panels, the A8 tips the scales at a sturdy 2095kg, yet Audi says the A8 will accelerate from 0-100km/h in just 5.9 seconds. And with 600Nm of peak torque available across a flat plateau from 1750-3250rpm this big four-door gets up and goes hard when asked to. 

At more sedate speeds you’re occasionally reminded there’s a diesel engine under the bonnet, with that characteristic engine and exhaust noise only making their presence felt under pressure. 

In fact, under normal circumstances, noise, be it the engine, tyres or wind is minimal, thanks to a combination of the car’s aero-efficient shape, thick acoustic glass and other sound-deadening measures throughout the car.

The eight-speed auto transmission is suitably smooth, with the central shifter or wheel-mounted paddles able to make snappy sequential ‘manual’ shifts.

There are four drive modes in the ‘Drive Select’ system - ‘Comfort’, ‘Auto’, ‘Dynamic’ and ‘Individual’ - enabling tweaks to the steering, transmission, throttle and suspension. Comfort felt most appropriate most of the time, although dialling up the throttle and transmission to more aggressive modes in Individual adds an enjoyable edge.

The suspension is five-link front and rear with an adaptive air system smoothing even high-frequency bumps and ruts amazingly well.

Push into a corner and the A8 feels nicely balanced, its wide track, sophisticated suspension, plus the quattro AWD system seamlessly distributing drive between the front and rear axles, keeping the big body under control. In fact, you feel the ‘big car shrinking around you’ syndrome from the get-go.

The steering is precise without being overly sharp and road feel is good. Again, with that 2.1-tonne kerb weight in mind, braking is appropriately powerful with big ventilated discs front (350mm) and rear (330mm).

It pays to remember the turning circle is 12.5m, and it’s worth picking your spot for a U- or three-point turn.

Although there’s a lot going on for the driver in terms of screens, buttons and switches it all makes sense ergonomically. The head-up display is helpful and there’s a common sense mix of digital and physical controls, the latter including an audio volume knob. Yes.

Even though the A8 hasn't been assessed by ANCAP, as you might expect, it goes to town when it comes to active safety tech, the car’s standard crash-avoidance features including auto emergency braking (AEB) (pedestrians/cyclists - 5.0-85km/h, vehicles - to 250km/h), ‘Active Lane Assist’, blind-spot monitoring, a reversing camera and 360-degree view (including kerb view function), front and rear parking sensors, ‘Collision Avoidance Assist’ (steering assistance in critical situations), ‘Turn Assist’ (monitors incoming traffic when turning right), and rear cross-traffic alert. 

There’s also ‘Intersection Crossing Assist’, ‘Attention Assist’, tyre-pressure monitoring and an ‘Exit Warning System’ (detects cars and cyclists when opening doors). 

If all that isn’t enough to avoid a crash the airbag count runs to nine, including front and side bags for the driver and front passenger, side airbags covering the outer rear passengers, full length curtains and a front centre airbag to minimise head clash injuries in a side impact. A first aid kit, warning triangle and high visibility vests are also on-board.

There are three top tethers for baby capsules/child seats across the back seat with ISOFIX anchors on the outer positions. 

Like all Mercedes models, the CLA 45 S comes with a five-year/unlimited-kilometre warranty, which sets the standard in the premium market. Better yet, five years of roadside assistance is also bundled in.

CLA 45 S service intervals are every 12 months or 20,000km, whichever comes first. A three-year/60,000km capped-price servicing plan is available for $3750, which is not cheap. That said, its pricing can be reduced by $750 if paid upfront alongside the vehicle.

The A8 is covered by Audi Australia’s five-year/unlimited km warranty, which is now par for the luxury market course, and 24-hour roadside assistance is included for the duration.

Paint defects are also covered for five years, with rust (to the point of perforation) covered for 12. Nice.

Service is required every 12 months or 15,000km with a five-year capped-price plan for the A8 coming in at $3830, or $766 per year. That’s a fair wedge but not outrageous for the category.