Audi A6 vs BMW Alpina B4

What's the difference?

I was thoroughly impressed by the Audi A6 Allroad 45 TDI quattro 2020 model. It is excellent on road, resolved and comfortable on unsealed surfaces, and very well packaged for family touring.

I’d personally have it in a heartbeat over a Q7 or any SUV, for that matter. I can understand why some buyers wouldn’t consider it, but if you’re someone who likes to think outside of the boxy SUV, then be sure to take a look at the Audi A6 Allroad.

You could almost call the B4 S the anti-M4. It's still fast and practical but from a completely different perspective. It's much more a grand tourer than the M4 and even with the Akrapovic exhaust (usually a byword for joyous, anti-social racket), subtle.

For some, the price won't matter because the Alpina delivers what they want - M4-like straight line performance without the histrionics or the uncompromising chassis. And there's also a bit of that perverse exclusivity of the styling that you won't get anywhere else.

If this isn’t the best looking genre of car, I must have been blindfolded since birth. You might think differently - be sure to let me know in the comments section below.

But for me, I just love the idea of a station wagon that is beefed up with SUV styling cues, and the Audi Allroad formula has been en pointe for generations now. This latest A6 Allroad doesn’t disappoint, either, with all the elements you’d expect.

Things like the bulging contrasting wheel-arch liners, the rugged underbody protection bash plates, and even the silver roof rails and silver metallic side sill protectors with ‘quattro’ emblazoned upon them - it just all works. 

And being an Audi A6 wagon underneath the glittery bits, it’s a sizeable vehicle. The dimensions read like so: length - 4951mm; wheelbase - 2925mm; width - 1902mm; height - 1458mm, though that depends on the height of the air suspension. 

The A6 Allroad sits about 45 millimetres higher than the standard A6 Avant wagon (not sold in Australia). And the ground clearance also varies depending on the air suspension height setting, but it is officially recorded at 139mm - which isn’t very high at all, but that’s for the regular driving setup. In its raised height, that jumps by 45mm to 184mm. Nowhere near an off-road Toyota, but still high enough to stop the belly from scraping.

And there are other hardware bits to help you out if the going gets tough - out of sight is Audi’s ‘quattro’ all-wheel drive system with a self-locking centre differential that the brand says provides “superior traction and its high level of safety and agile handling”. There is hill descent control, and the infotainment screen can display the location, elevation, compass and driving angles, too.

As for the design of the interior? It’s high-tech Audi opulence and comfort at its best. Check out the interior pictures to see what I mean.

Alpina has always had a particular aesthetic that could uncharitably be termed as mid-'80s West German - all set square angles and body graphics. Think David Hasselhoff's Berlin Wall look. The company has never really deviated from adding squared-off body bits to the various BMWs it has rebadged under its long-running agreement.

For the B4S, Alpina adds the signature billion-spoke alloy wheels (only a slight exaggeration), a new front splitter complete with Alpina lettering, a weirdly proportioned boot lid lip spoiler and - not even joking - pinstripes. Like I said, mid-'80s West German. You can still recognise the sleek 4 Series Coupe but perhaps the worst of it is the super-sized, wonky-looking ALPINA B4S on the boot.

Inside is rather more restrained apart from the ill-fitting Alpina plaque under the climate control. Again, it's all 4 Series in here, with the lovely Merino leather liberally applied across the cabin. Less lovely is the wood on the door pulls and console but the door cards have an oddly appealing woven leather which looks and feels good.

Sadly the standard 4 Series steering wheel is along for the ride. There's nothing wrong with it - although the Alpina logo does look out of place - but if I were a product planner, I'd beg for the lovelier M wheel.

Technical. Practical. Glorious. Three words I’d use to describe the cabin of the Audi A6 Allroad. 

The cockpit isn’t anything out of the ordinary for an Audi of the modern era, and as such it will feel familiar to you if you’ve been in or around any of its more recent stablemates. It also means that you’ll find yourself in a high-end, high-tech and highly pleasant interior. The materials used are beautiful and of a high standard. They look very nice and it is an extremely pleasant place to be. And you can hate on me if you want, but I’m sold on brown leather. Yummo!

It will take some time for you to get to grips with the dual-touchscreen layout of the cabin, but once you get the hang of it, it becomes second nature.

The media screen is very easy to use, the menus are simple to learn, and over my week there were absolutely no issues with Apple CarPlay - either when connected via USB, or when used wirelessly.

The second screen below controls a lot of the main functions of the air conditioning system, and while I’m not a huge fan of using a screen to touch through temperature and fan controls, this one has haptic feedback and is well positioned - it’s not as much of a glance away from the road as in, say, a Land Rover or Range Rover. There’s also a volume knob which is good, and quick buttons for Drive Select and demister for front and rear windscreens.

In terms of the practicalities, there are bottle holders in the doors, a pair of cup holders between the front seats, a covered centre console bin with Qi wireless phone charging (remember not to leave your phone in there!) and there are two USB ports in there, plus a SIM card slot and SD card slot as well.   

The seat comfort is very good - there’s electric adjustment on both seats with lumbar adjustment, and the driver’s seat gets memory settings as well. The electric steering wheel adjust is a nice touch as well, and there’s a remote boot release trigger, too.

There are twin sunroofs, and the front one can tilt and slide while the rear one is fixed. It helps lighten things up a bit if you have the optional dark headlining, which I personally wouldn’t choose.

Rear seat space is excellent. Sitting behind my own 182cm driver’s seat position, I had easily enough legroom, headroom and shoulder room - in fact, the rear pew is so accommodating, it could easily fit three of me across - but foot space is a little tight due to the large transmission tunnel. 

Those in the back are well catered for – there are 2x USB ports, a pair of large door pockets with bottle holders, twin mesh map pockets, a flip down armrest with storage and cupholders, and our car had quad zone climate control (as part of the optional Premium Plus package - standard is three-zone climate), plus there are centrally mounted directional air vents and in the door pillars at face height. Our tester also had those optional manual sunblinds, which would certainly help those in the back get some shut-eye on longer trips. 

The centre section of the rear seat can be split folded down on its own as well – so you have 40:20:40 rear seat folding, which is great for skis or snowboards. Plus there are two ISOFIX child seat attachments and three top-tether points available for baby seats. And one of the most excellent additions to any car ever – illuminated seat belt buckle receivers. It just makes it that much easier to see at night.

If you need to fold down those rear seats, there are boot-mounted triggers. That’ll help expand the luggage capacity from the standard 565 litres (VDA) to an expansive 1680L (VDA). The cargo hold easily fit the three CarsGuide suitcases (124L, 95L and 36L) with room to spare.

There is no Audi Allroad seven seater, though. And that’s potentially where something like a Q7 makes more sense, depending on your intent. 

If you're in the front, you're in luck - it's a comfortable place to be, with plenty of leg and headroom. Down back isn't terrible despite the coupe roofline. The two seats are nicely shaped for maximum comfort and separated by an odd plastic tray. The fold-down armrest has two cupholders.

Front seat passengers score a pair of cupholders (bring the total to four for the car) and the long doors will hold a bottle each.

The boot swallows a reasonable 445 litres, which isn't at all bad.

If you thought BMW don't mess about when pricing up its cars, you best strap yourself in. The 440i-based B4S starts at a solid $149,900. That's $48,000 more than the 440i and significantly more than an M4 Pure. But there's plenty of gear on offer and some genuine, bespoke Alpina additions.

Standard are 20-inch signature Alpina alloys, 16-speaker harmon kardon-branded stereo with DAB, super-soft Merino leather everywhere, dual-zone climate control, around-view cameras, reversing camera, sat nav, keyless entry and start, front and rear parking sensors, active cruise control, heated and electric front seats, head-up display, auto headlights and active LED headlights, LED taillights and electric sunroof.

The stereo and sat nav are run by BMW's iDrive. It's a cracker of a system and almost gets away without Apple CarPlay and Android Auto. The absence of such simple pleasures at this price point is a bit lame, but here we are.

Under the bonnet of the Audi A6 Allroad is what Audi labels the ‘45 TDI’ - a 3.0-litre turbo-diesel V6 engine that produces 183kW of power (from 2750-4500rpm) and 600Nm of torque (from 1500-3000rpm).

The engine is only available mated to an eight-speed torque-converter automatic transmission and Audi’s renowned ‘quattro’ all-wheel-drive (AWD) system. 

Audi claims this 1980kg wagon can run from 0-100km/h in just 6.5 seconds, on its way to a top speed of 250km/h. It is a hummer of an engine - more on that in the driving section below.

Towing capacity is pegged at 750kg for an unbraked trailer, and maxes out at 2500kg for a braked trailer.

Should Aussies feel short changed when it comes to the engine options here? Arguably, yes - and that’s despite the powertrain offered here still being a stormer. 

There’s only one spec available Down Under, and even it doesn’t get the most up-to-date emissions tech. There isn’t AdBlue urea treatment (meaning this is a Euro 5 engine), and our cars have essentially been de-specced to miss out on the latest 48-volt mild-hybrid tech, which is standard on all grades of the A6 Allroad in Europe. Maybe that is part of the reason the cost is down, this time around. 

And while the outputs of the 45 TDI in Australia are pretty decent, other markets have the A6 Allroad offered in 50 TDI (210kW/620Nm) and 55 TDI (257kW/700Nm) trims. Remember, though - this is a very niche player here. 

A lot of your extra money turns up under the bonnet. These days the 440i packs BMW's slick B58 turbo straight six and the B4S does likewise. The boys from Buchloe in Bavaria (there are certain to be women there, too, I just liked the alliteration) added a pair of Alpina-spec turbos to generate a whopping 324kW and, more importantly, 660Nm. Alpina says 600Nm (the max torque figure of the brilliant M4 CS) is available from 2000-5000rpm, while the full 660Nm is available from 3000 to 4500rpm.

The M4 Pure has 317kW and 550Nm from the S55 straight-six. Just so you know.

Like the 440i but unlike the M4, the B4S employs the dependably brilliant eight-speed ZF automatic found throughout the BMW range.

Audi claims the 45 TDI powertrain in the A6 Allroad will use 6.6 litres per 100 kilometres. That’s the official Australia fuel consumption figure on the combined-cycle test. CO2 emissions are claimed at 174g/km.

During my time in the Audi A6 Allroad I saw an average fuel use return of 7.4L/100km - which was taken over highways, back roads, unsealed roads and twisty bits. There was even some urban stop-start in there, too. I think that’s pretty darn good for a car of this size.

Fuel tank capacity is 63 litres, meaning a real-world range of 851km based on my fuel consumption.

As mentioned above, the A6 Allroad is a mild hybrid model in other markets, but not in Australia. We don’t even get the Euro 6-compliant version here, as there’s no incentive for it to be offered locally - as in, there’s not even AdBlue treatment. 

There’s no electric version (though you might want to look at the all-new Audi e-tron)  or plug in hybrid, and no petrol model either.

Alpina quotes 7.9L/100km on the combined cycle and we went through the premium unleaded at the rate of 11.7L/100km. I enjoyed myself, so that's not a terrible result.

Here’s where the A6 Allroad separates itself from, say, an Audi Q5 or Q7. It’s a low-slung wagon, made for touring on country roads, doubling down on dirt backtracks and cruising comfortably on the freeway.

It’s not as upright as a Q5 or Q7, and that means it has a lower centre of gravity - so it feels more hunkered down, more settled into the surface below.  

And in the case of the A6 Allroad, there’s adaptive air suspension all around to cushion the car from what lies beneath. For the most part, that air suspension is superb - it absorbs big bumps and lumps very well, though the oversized 21-inch optional wheels can’t disguise sharp edges from those in the cabin. 

The general compliance is very good, and as I found out first hand, you can easily soak up hundreds of kilometres without feeling the affects of the road underneath you - even over bumpy country back roads and lumpy dirt sections.

The steering could be better; it’s a little bit vague and heavy on centre at higher pace, but at lower speeds it is light and amicable. Very easy to park despite its size, and easy to manoeuvre around town, too.

The engine builds pace with superb linearity, and it’s very quiet and refined as well. There is a tiny bit of turbo lag at lower speeds or from a standstill – but it is completely manageable and never feels like it’s sluggish at all. The 0-100km/h claim of 6.5 seconds seems achievable, too. 

The eight-speed automatic transmission was mostly very smart and well sorted - although in other VAG models with this engine family/eight-speed auto, the transmission never felt quite as busy at higher speeds. I noticed it shuffling between seventh and eighth gears more than I was expecting, given how much torque the engine has. It’s not annoying at all, and nor is it unrefined, and could well have something to do with attempting to save fuel rather than leaving it in top gear.

During night driving, the optional HD Matrix LED headlights were exceptional - among the best headlight technology that I’ve ever encountered. The ‘matrix’ technology means they can blank out oncoming traffic or cars in front of you while keeping the high-beam on in other areas. The auto headlights with auto high beam worked very well, too.

The plan was never to do a serious off road review, but I did do some driving on unsealed roads and found the Allroad to be excellent. 

Through slippery unsealed corners it exhibited excellent traction, though you can feel the weight of the car shifting from side to side when you pivot through corners. There was a touch of skittishness over mid-corner bumps, but again that could be more to do with the big wheels than anything else.

I came away thinking that if you had your eyes closed, you wouldn’t even know that you were on dirt or gravel. It really is an exceptional car across sealed and unsealed roads. 

One of the key differences between the B4 and M4 is the ride. While the M4 can crash over bumps and generally be a little hard to live with, the crew in Buchloe have gone after a much more plush ride. And in that they have succeeded because the B4 S is a mighty fine cruiser. Bumps are dismissed with a haughty disdain, even Sport + silliness doesn't completely write-off ride quality.

Very impressive too, is the steering. While still not at Lotus Elise levels of feel (few cars are), the Alpina tweaks connect the your palms to the road with more clarity than what you'll find in the 440i or M4. Where the M4 particularly adds too much weight, the 440i is a bit more circumspect in that regard.

And then we come to the engine. The B58 six is a belter, better even than the N55 that preceded it. It's still a 3.0-litre straight six but is part of BMW's modular engine family that starts with a 1.5-litre triple in the Mini and 1 Series. The Alpina-spec turbos are noisier, the Akrapovic exhaust lighter and also noisier. It doesn't have the all-out crackle and pop of an Audi or Merc (perish the thought), but when you're on it, the B4 means business. The 660Nm of torque, available over a wide rev range, delivers a steel fist wrapped in a velvet glove and bubble wrap - the speed builds rapidly but smoothly. 

The approach to the chassis tune seems to be based on the driving talents of mere mortals on normal roads, which is kind of like the 440i. It's terrific fun to drive hard but it's very forgiving and patient. The great thing about it is that you wouldn't think twice about jumping in it for the long haul, so comfortable and quiet is the cabin. The M4 will leave it for dead on a winding road, but that's perfectly fine.

One irritant is the replacement of the admittedly cheap BMW gearshift paddles with weirdly non-tactile buttons. They're not particularly easy to use and, probably worse for a sporty car, unsatisfying. It's an odd detail with which to go off the reservation. Cheeringly, the eight-speed ZF is its usual perfect self, so you don't have to worry too much about manual mode or go old school and use the shifter.

The Alpina ships with six airbags, ABS, stability and traction controls, ABS, stability and traction controls, forward collision warning, forward AEB, road sign recognition and active cruise control.

There are also two ISOFIX points in the rear. Neither the Alpina nor the 4 Series has an ANCAP safety rating.

Audi offers a three-year/unlimited kilometre warranty, which is as good as BMW, but not as good as Lexus (four years/100,000km) or Mercedes-Benz, Volvo and Genesis (five years/unlimited kilometres). It’s falling behind in the luxury sphere.

The company offers reasonably priced capped price ownership plans for maintenance. Purchasers can roll in the cost of either a three-year service plan ($2170) or a five-year plan ($3300). That covers off the usual service items due every 12 months/15,000km.

Roadside assist is included for the period of the new car warranty.

Alpina offers a two-year/unlimited-kilometre warranty which is a bit behind the times and not in keeping with the price point. Servicing is another matter altogether and you're subject to your dealer's standard charges for servicing.