Audi S5 review

On the face of it, the Audi S5 looks like a stylish and suitably sporty coupé. But if you’re imagining a bone-shaking ride and an engine that drinks fuel faster than a Formula One car, this Audi A5 variant might surprise you.

You see, unlike the range-topping Audi RS5 – which is all about performance – the S5 is a surprisingly easygoing companion that has a diesel engine capable of averaging more than 40mpg. It’s still very fast, mind.

The Audi S5 is available in swoopy three-door form as well as more practical five-door Sportback guise. However, underneath it’s essentially the same car as the Audi S4 (which is available in saloon and Avant – estate car – forms).

Audi’s choice to stick a diesel engine until the bonnet instead of a petrol or a hybrid powertrain might seem a bit outdated, but as well as surprisingly good fuel economy, the S5 can manage huge distances without stopping for fuel.

Does that make the Audi S5 a better choice than its closest rival, the petrol-powered AMG C43 version of the Mercedes C-Class Coupé? That's what we'll tell you over the next few pages of this review. We'll cover performance and handling, comfort and practicality, running costs and more.

Once you've picked your next new car, make sure you get it for the lowest price by searching our free What Car? New Car Deals pages. They list plenty of the best new coupé car deals.

The S5’s 3.0-litre V6 bi-turbo diesel engine is seriously sophisticated. It has a 48-volt electrical hybrid system that powers an electric compressor, which works alongside a regular turbocharger to give a total of 345bhp and 516lb ft of shove. And because the latter is available from just 1500rpm, the S5 isn’t just faster than a Kia Stinger GT S in a straight line – the 0-62mph sprint is over in 4.8 sec – it’s also a far more flexible performer. In fact, it’s almost as rapid as the AMG C43 Mercedes C-Class Coupé.

Sadly, the driving experience is blighted by a laggy and unresponsive automatic gearbox. The noticeable delay when you put your foot down frustrates when trying to dive for gaps on roundabouts; the S5 lurches forward suddenly when the power does eventually arrive. Thankfully, this hesitance can be reduced slightly by knocking the gearbox into its ‘Sport’ setting, or by using the steering wheel-mounted paddles to preselect a gear.

If you’re worried that a diesel won’t be a patch on the petrol six-cylinder engine in the C43 when it comes to noise, don’t be so hasty. Thanks to an electronic sound generator (read fake exhaust sound) it sounds more like a petrol V8, but without seeming too contrived like some similar systems can. The engine quietens down at a steady cruise, though, and there’s little wind and road noise.

As is the case with the C43, power is fed to the road through all four wheels. As a result, the S5 never struggles for traction – even when the road is wet. It can go around corners suitably quickly, too, but you won’t have a great deal of fun when doing so; the Alfa Romeo Giulia Veloce and even C43 are more rewarding to drive quickly along a winding road, thanks to their more playful handling and more feelsome steering.

Ride comfort is generally good, though, so when viewed more as a grand tourer that happens to be very fast, the S5 has a lot going for it. The Vorsprung version wafts along particularly smoothly, thanks to its standard adaptive suspension.

The S5’s interior isn’t that different from the one in the regular Audi A5, although that’s no bad thing. Its design is relatively conservative and, as standard, the colour scheme is mostly a combination of dark greys and blacks, with some alloy trim on the face of the dashboard. However, you can opt for light grey or even bright red seat seats if you want to liven things up a bit. 

Expensive Nappa leather graces the seats whichever colour you choose, those in the front being more supportive than those in the regular A5, firmly holding you in place when cornering at speed. The front seats are also electrically adjustable, with four-way lumbar support and even a massage function to soothe you on long journeys.

Everything you touch feels expensive enough to justify the price, and the buttons and knobs feel reassuringly solid when you use them. In short, the S5 is classier inside than its closest rivals, the Kia Stinger and AMG C43 Mercedes C-Class Coupé.

Every S5 gets a 10.1-inch colour touchscreen on the middle of its dashboard. As touchscreens go, it's relatively well designed, with an intuitive operating system. But there's no doubt it's more distracting to use when you're driving than the systems in some rivals, including the C43 or any BMW.

All S5 models also get a 12.3in screen behind the steering wheel in place of a traditional analogue speedo and rev counter. Dubbed Virtual Cockpit, this configurable screen can show full-screen sat-nav maps as well as other important driving information. The S5 has a specific ‘S’ arrangement for the screen, dominated by a big central rev-counter, a bit like in the Audi R8 supercar.

You're unlikely to consider the coupé version of the S5 if space is your top priority, but it isn’t as impractical as you might imagine. There's certainly plenty of front space; even if you’re extremely tall you’re unlikely to have any complaints about how far your seat slides back or how much room there is above your head. A couple of six-footers will fit in the back, too, although they’ll have to slouch to keep their heads from brushing against the ceiling.

In fact, even the Sportback version, which has rear doors, isn’t exactly palatial in the back, but access is obviously much easier so it’s worth the relatively small premium if you plan on carrying people in the back more often than just in emergencies.

Officially, there’s more boot space than in an AMG C43 Mercedes C-Class Coupé and, while the differences are small, its load bay is certainly usefully squarer than those of its key rivals. Rear seats that split and fold 40/20/40 are standard and, when down, leave only a gentle slope in the floor of the extended load bay.

The S5 has a much lower starting price than the rival AMG C43 Mercedes C-Class Coupé but the Kia Stinger is considerably cheaper than both cars. However, if you go for the range-topping Vorsprung version of the S5, which has just about every option box ticked, the price swells above that of all key rivals.

We wouldn’t bother with the Vorsprung, because the S5 is well enough equipped as standard. Standard luxuries include 19in alloys, self-dimming LED headlights, front and rear parking sensors and leather seats. Consider adding the Comfort & Sound Pack if you want a few more creature comforts.

Although diesel isn’t the most fashionable fuel at the moment, it still has some big advantages over petrol. For one thing, diesel fuel economy tends to be much better, and the S5 officially averages just over 40mpg. In the real world, 35mpg should be easily achievable as long as you don’t use the S5’s prodigious performance too often.

That good fuel economy, combined with a relatively large fuel tank, means the S5 can also travel much farther between fill-ups than any of its key rivals. However, the relatively unpopularity of diesel at the moment probably explains why the S5 isn’t predicted to hold onto its value as well as the C43, although it won’t depreciate as quickly as the Stinger.

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