Audi S4 Avant estate review
The Audi S4 Avant offers huge pace and space with subtle looks, but we wish it was more fun to drive
- Huge grip in corners
- Reasonable fuel-efficiency
- Lots of space
- Diesel engine note
- Lacks driver involvement
- Expensive optional extras
The Audi A4 saloon and Audi A4 Avant estate are respected compact executive cars that can be chosen with a choice of pretty powerful petrol and diesel engines. The Audi S4 is also on hand to satisfy those who want a little more power and sportiness than the A4 can offer, and is available as a saloon (which we’ve reviewed separately) and this smart Avant estate version.
Audi has offered a performance S4 version of the A4 since the late nineties and in every case it has packed a healthy dose of extra power and handling prowess on top of the historical A4 attributes of crisp design and high quality inside and out – as well as the allure of that four-ringed emblem on the nose.
The S4 is not without rivals – BMW offers the rapid M340i and M340d xDrive versions of the BMW 3 Series Touring, and the Mercedes C-Class Estate can be chosen in AMG C43 specification. Nor does Audi’s quattro four-wheel-drive system put it at an automatic advantage like it used to – the BMW and Mercedes both come with four-wheel drive these days.
While previous generations of the S4 were powered by a range of six and eight-cylinder petrol engines, the latest model boasts a turbocharged 3.0-litre V6 diesel engine producing 336bhp. Power and performance are the main attraction of the S4 saloon and the Avant adds an impressive amount of extra practicality to make it a more practical car to live with. It's also a diesel among petrol rivals, so its official fuel-efficiency figure of 38.7mpg will appeal to high-mileage drivers put off by the 28mpg of the Mercedes-AMG C43. You could also argue the Avant is better-looking than the saloon, but it’s also around £1,500 more expensive.
It does have a fantastic interior, though, with loads of space in the front and back, and the materials used are some of the finest you’ll find in any car. However, passenger comfort is partially sacrificed on the altar of performance – the suspension is firm and the ride can be bumpy at low speeds.
For buyers who want more performance, the RS4 Avant is powered by a 3.0-litre twin-turbocharged petrol engine producing 444bhp. Costing around £14,000 more to buy, it’s quicker but it will be a lot more expensive to run, managing around 26mpg. For most drivers, the S4 Avant should offer more than enough speed and practicality with more affordable running costs.
The standard Audi A4 fared poorly in our 2020 Driver Power owner satisfaction survey of cars currently on sale in the UK.
MPG, running costs & CO2
The Audi S4 Avant benefits from a modern design and sophisticated mild-hybrid diesel engine when it comes to running costs. Naturally, it’s not as frugal as its less powerful diesel-engined brethren, but on the face of it, 39.7mpg isn’t at all bad for a 336bhp estate car. It’s nearest diesel-powered rival is the BMW M340d xDrive Touring, which is capable of similar performance and fuel economy of around 44mpg, but costs around £4,000 more to buy. When compared to petrol rivals such as the Mercedes-AMG C43 (28.8mpg) and the BMW M340i xDrive Touring (33.6mpg), the S4 looks positively frugal by comparison.
The S4 Avant’s CO2 emissions figure of 191g/km is fairly high, placing it in the top Benefit-in-Kind (BiK) band for company-car drivers. Road tax is £465 a year, made up of a £140 yearly flat rate, plus a £325 additional charge levied on cars costing £40,000 or over. This additional charge applies for the first five years of ownership.
Other running costs shouldn’t be too much greater than other members of the A4 range, although expect tyres and brakes to require regular replacement if the heavy S4 is regularly driven hard – and neither will be cheap.
Engines, drive & performance
The greatest weapon the Audi S4 has in its performance arsenal – even overshadowing the huge amount of power on offer – is the sheer grip provided by its wide tyres and quattro four-wheel-drive system. It really does remain firmly nailed to the road even in very fast corners and won’t deviate from the course you choose.
It’s a bit of a letdown, then, to find that the steering is rather uncommunicative. Turning it gets results, but doesn’t reward or inform you as to how close to the limit you’re getting. Fortunately, the limits of grip are so high this is unlikely to become a safety issue, but the S4 would inspire greater confidence if the steering offered a little more feel.
Power certainly isn’t in short supply – the 3.0-litre turbocharged diesel engine develops 336bhp and has a broad spread of pulling power, thanks to an electric compressor that assists the engine as soon as you hit the accelerator. thrusting The S4 gets from 0-62mph in just 4.7 seconds, making it a tenth of a second faster than the diesel M340d xDrive Touring, and just behind petrol rivals like the M340i xDrive Touring and Mercedes-AMG C43 4MATIC that are both a tenth faster still. Its rivals also sound more exciting, with the S4 producing a slightly muted rumble as you accelerate.
However, it doesn’t do anything to help you feel more engaged in the process and the S4 falls short on driver appeal in comparison to its BMW rival. However, this feeling of being slightly removed from the action also has the effect of making the S4 quite a relaxing car to drive – it could be argued that the S4’s forte is actually in being an ultra-high-speed family cruiser. The car is still capable of slingshotting out of corners, however, thanks to an electronic sports differential.
With a Drive Select system through which chassis and steering settings can be chosen, the S4 is at its most responsive on the sportiest settings, yet in Comfort mode you don’t lose any of the power and traveling on fast roads is a comfortable experience.
Interior & comfort
Fast Audis have often been criticised for a harsh ride quality and although the S4 saloon felt smooth when we tried it on European roads, on the broken, rutted tarmac of the UK it can be rather fidgety. Bumps and imperfections in the road are never really concealed at moderate speeds and potholes can make life for passengers less than luxurious – even with the suspension in comfort mode.
You can choose an adaptive damping system as a £900 optional extra and this helps to some extent, but given that our test car was fitted with the smallest 18-inch wheels, which we thought would provide a smoother ride, it’s questionable as to how much of an improvement it makes.
The ride is less bothersome at higher speeds and there isn’t a lot of noise from the tyres, either – further qualifying the S4 as an express cruiser. It’s when the car quietens down that you’re better placed to enjoy that traditional field of Audi excellence – a beautifully assembled and lavishly trimmed interior.
High-quality materials and common-sense design abounds and there’s as much standard equipment as you could ask for, including sat nav accessed through a 10.1-inch colour display – as we would expect in what is a range-topping car. Audi's Virtual Cockpit system is also standard, so the conventional instruments are replaced by an electronic display that can show whichever information you want, including navigation directions on a large, detailed map.
Other standard S4 Avant equipment includes 19-inch alloy wheels, LED headlights and rear lights, a rear-view camera and an upgraded smartphone interface with Apple CarPlay and Android Auto. Buyers can also upgrade to the S4 Avant Black Edition, adding bi-colour alloy wheels, a black exterior styling pack, piano black interior trim and a flat-bottomed steering wheel.
S4 Avant Vorsprung adds to the standard equipment list further still with unique 19-inch alloy wheels featuring a matte titanium finish, a panoramic sunroof, Audi’s Driver Assistance Pack, extended LED interior lighting and a premium Bang & Olufsen 3D stereo system.
Practicality & boot space
The Audi S4 Avant isn’t a small car. It’s actually marginally bigger than the BMW 3 Series Touring and Mercedes C-Class Estate. This helps the S4 to offer more space and practicality than its rivals, both in the passenger compartment and the luggage bay.
The front seats offer plenty of space for drivers and passengers of most sizes and there’s loads of adjustment in the driver’s seat and steering column. The sports seats are well padded and bolstered. Two adults or three children will be comfortable in the back, and neither front nor rear-seat passengers are likely to be short of headroom. The middle rear-seat occupant might struggle for somewhere to place their feet owing to the transmission tunnel passing, but this is also a problem in the BMW 3 Series and Mercedes C-Class Estate.
ISOFIX child-seat mountings are provided on the front passenger seat as well as the two outer rear seats. You’ll find plenty of cubbies and pockets for storage of small items – two front cup-holders, door pockets, a central storage bin and a glovebox that a large bottle of water will fit in with ease.
The S4 Avant does rather well in the luggage-handling department, too. You have 505 litres of room with the rear seats in position, which eclipses its BMW and Mercedes rivals. It expands to 1,510 litres with the seats folded down, compared with 1,480 litres for the Mercedes C-Class. It’s an intelligently shaped boot, too, with a low loading lip, fold-away hooks and a storage net to prevent loose items flying around under spirited cornering. It’s well illuminated, too, with LED strips along either side. A minor demerit, though, is that the seatbacks don’t fold entirely flat.
Reliability & safety
Safety is never an area where Audi cuts corners and there’s no danger that the company would choose to start doing so in a high-performance estate car. The S4 hasn’t itself been tested by independent crash safety experts Euro NCAP due to the comparatively small numbers in which it sells. However, the A4 it’s based on has an exemplary safety record.
The A4 received a full five-star rating, scoring 90% for adult occupant protection and 87% for child occupant protection, thanks in no small part to six interior airbags, with a pair of rear-seat airbags available as an option. Pedestrians are also protected by an ‘active’ bonnet that can raise in an impact to prevent them striking hard points under the bonnet. There’s also an autonomous emergency braking system, which is active at the kind of speeds you expect to travel at in urban areas.
The standard Audi A4 was rated poorly for reliability in our 2020 Driver Power owner satisfaction survey of cars currently on sale in the UK. Of the owners who responded, 20% reported experiencing a problem with their car at least once.