2012 Audi A6 vs. 2011 BMW 535i Road Test

Who Will Protect the 5 Series Legacy?

Published: 12/21/2011  - by Erin Riches, Senior Editor

BMW has defined the rules in the midsize luxury sedan class for some time now. If the executives in Munich decide the 2011 BMW 535i should be quieter, gentler and less focused on performance, we half expected everyone else to follow suit.

But Audi didn't. The redesigned 2012 Audi A6 3.0 TFSI Quattro goes through a corner like no A6 before it, accelerates hard in a straight line and feels a lot like the 5 Series we used to love. But this isn't some one-dimensional homage, as Audi has also loaded the A6 with leading-edge technology to appease modern car guys and their iDevices.

And just like that, the 2012 Audi A6 has become the most desirable car in the midsize luxury sedan class, leaving the 2011 BMW 535i in the unfamiliar position of 2nd place.

I'm Your Biggest Fan
With this redesign, the A6 finally joins the A4, A5 and A7 on Audi's MLB chassis. It mounts the engine longitudinally, but places it farther back behind the front axle to lessen the sensation that you're in a front-drive-based Audi instead of a rear-wheel-drive Bimmer.

Notably, this A6 has 3 fewer inches of front overhang, which translates to less mass up front and helps the car respond more quickly to steering input. All A6s with the 3.0 V6 also get standard Quattro all-wheel drive. Its torsen-type center differential biases 60 percent of engine torque to the rear axle, so it steers more naturally under normal conditions.

Even with its all-wheel-drive hardware, the 2012 Audi A6's curb weight is within the BMW's ballpark. The use of aluminum body panels and suspension parts holds our Audi A6 tester to 4,175 pounds — just 100 more than the rear-drive 2011 BMW 535i. The two cars are within an inch of each other in length, width and height, while the BMW has an extra 2 inches of wheelbase (116.9 inches).

I Heart Forced Induction
Anyone would have a tough time coming up with an engine worthy of competing with BMW's turbocharged inline six-cylinders. The smooth, refined engines deliver the goods when you floor the throttle, while serving up a sweet soundtrack of induction noise and exhaust snarl.

The 3.0-liter N55 six in the 2011 BMW 535i uses one twin-scroll turbocharger, plus direct injection to get an easily verifiable 300 horsepower and 300 pound-feet of torque. Not only does our 535i feel great, it puts up the same acceleration numbers as the V8-equipped BMW 540i of a decade ago.

The Audi's 3.0-liter V6 engine has more low-end grunt, though, if you don't mind its industrial drone. Response is sharp off the line, and then it delivers a torque curve as broad as Montana. You don't expect performance like this from a V6 (forced induction or not) and neither do the motorists you've just blown by on the freeway.

What's more, the Audi's supercharged V6 is listed at 310 hp and 325 lb-ft of torque, but we suspect it's even more underrated than BMW's turbo inline-6s. Why? Its quarter-mile time is a half-second quicker and its trap speed was 102 mph, 5 mph faster than the 535i. The A6 is also half a second quicker to 60 mph at 5.2 seconds (or 4.9 with 1 foot of rollout like on a drag strip).

Eight Speeds for All
Both sedans use the ZF eight-speed automatic transmission (though you could order a six-speed manual on the 2011 535i). Forward gearing is nearly identical, but the sedans' final drives are different, and of course, each manufacturer uses it own proprietary software.

In their respective sport modes, both automatics upshift smoothly under full throttle and downshift with authority, not to mention matching revs to keep things smooth. In Manual mode, the A6 upshifts for you before the rev limiter, which is more of a poetic injustice than a real problem when you have an engine that's all about the midrange.

The 535i is plagued by the same sluggish response to part-throttle inputs we've observed in a few other BMWs like our long-term 528i, our long-term 750i and the 2011 740i. It's hard to be smooth in city traffic, so we hope BMW will address this soon.

Red Alert: We Don't Have Pricing Parity
Although we matched the cylinder counts and transmissions on these midsize luxury sedans, our 2011 BMW 535i test car costs $60,225, while our 2012 Audi A6 3.0 TFSI Quattro comes in at $71,330.

How do we live with ourselves? Simple math. The base prices on these sedans are within $300 of each other, but this particular 535i is an austerity special. It has the Sport and Dynamic Handling packages and à la carte Dakota leather, but no Premium package, no navigation system, not even an auto-dimming rearview mirror.

If you option the 2011 BMW 535i up to the level of our A6 tester (Prestige, Sport and Innovation packages, plus the Bang & Olufsen philharmonic), it finally arrives at $71,920, a difference of $590.

Taking the Back Road to Work
For this kind of money, you want more than a nice daily driver — you want a sedan that takes you on an adventure. That's the reason we've always liked the BMW 5 Series. But this time around, we have to admit that if construction forced us onto a back road, we'd rather be in the A6.

Earlier A6s were clumsy when you got them on a good road, but this one feels light and changes directions easily. The 255/40R19 Pirelli P Zero Sport package tires certainly help with grip, but there's a solid suspension underneath this car as well. It gives the A6 excellent balance and makes you feel as if your inputs matter. This builds confidence, and when you arrive at the corner exit, you can wood the throttle and take full advantage of the Audi's AWD.

This kind of feedback is what made previous 5 Series sedans so addictive, and it's exactly what's missing from the 2011 535i. The car put on nearly 200 pounds in its latest redesign and that, combined with its suspension's softer state of tune, makes for a far more isolating experience. This 5 Series still goes where you expect it to, but now you don't really know how it got there. You just assume the adaptive dampers and antiroll bars were working their magic.

The 535i also has less grip than the A6, which isn't surprising with its Goodyear Excellence run-flat tires (245/40R19 front, 275/35/R19 rear), which aren't known for their adhesion. Of course, this yields predictable results during instrumented testing, where the A6 goes through the slalom at 67.2 mph to the 535i's 64.5 mph. Skid pad results are closer, as the Audi manages 0.90g versus 0.88 g for the BMW.

I've Lost My Way
Without question, this 2012 Audi A6's electric steering is better than the setup we had in our long-term S5. The A6's steering is still overly light at low speeds, but the effort level increases in a more linear fashion when you start barreling down back roads. The steering ratio matches the quick reactions of the chassis, too. Still, we would prefer even more feedback.

Similarly, the steering feel that once distinguished the 5 Series from all other midsize luxury sedans is gone. Instead, this car has precise, electric power steering with a logical build-up in effort as you turn the wheel off-center. And that's it. Nothing wrong with it, but nothing special about it either.

Braking performance also inspires ambivalence. Pedal feel is soft in the A6, but it stops from 60 mph in 111 feet. The brake pedal is pleasantly firm in the BMW 535i, but with those Goodyears, it can't do any better than 118 feet.

Back on the Highway
We expect cars in this class to spare us every discomfort. But that's no easy task with 19-inch wheels, low-profile tires and notoriously lumpy L.A. freeways.

Although both sedans have compliant rides, there's more impact harshness than we'd like, particularly in the A6, which isn't available with adaptive dampers. Forgoing the optional Sport package suspension calibration might help, but it would make the A6 less fun through corners.

Inside, both driver seats are comfortable and supportive, but the BMW's chair is wider with an extendable seat-bottom cushion, and is therefore more accommodating for 6-foot 200-pounders.

If you're going to use the backseat, we'd lean toward the Audi, which has significantly more real-world rear legroom than its 1.3-inch advantage would indicate. In addition, the A6's narrower front seats benefit rear passengers, who have a better view out the front of the car.

Silicon Valley in Your Sedan
Technology is no longer an afterthought in sport-luxury sedans like these. Now you practically need basic computer skills just to drive them.

BMW's iDrive has come a long way on the user-friendliness spectrum, but it still reminds us of Internet Explorer: In other words, it's still a bit clunky. In the A6, corner buttons around the main Multi Media Interface (MMI) controller act as breadcrumbs, so it's easier to regroup if you've gone down the wrong path.

In addition, the BMW 5 Series doesn't have a Wi-Fi router, which is the neatest bit of tech in the 2012 Audi A6. Using a 3G connection (with a rated speed of 7 megabits per second), this mobile Internet connection adds Google Earth data to the navigation system's DVD-based street maps while providing simplified Google search for POIs. It sounds a bit over the top, but it's actually quite handy if you need to get some unexpected work done on the road and there's no Starbucks in sight.

Both cabins have rich wood inlays surrounding their tech, but the furnishings in the A6 are warmer than the down-to-business ensemble in the 535i. However, we noticed a couple ill-fitting panels in our Audi tester, while the BMW is flawless.

Are There Any Sport Sedans Left?
It's a stretch to call the Audi A6 and BMW 535i sport sedans. These are big, heavy, complicated luxury sedans, and comparing them to a seminal car like the E39 5 Series, which had a CD-based nav system and weighed 500 pounds less, seems almost silly.

Yet, the 5 Series is the car that made the midsize luxury sedan class cool, and BMW executives seem to have lost sight of that. There's nothing terrible about this softer, more luxurious 2011 535i, but it doesn't match its predecessor's braking and handling numbers, and more critically, it just isn't as fun to toss around anymore.

The Audi A6 has never been a player in this class — the 5 Series usually outsells it 4 to 1. But great things happen when an automaker has nothing to lose and this A6 feels like a winner.

This 2012 Audi A6 puts a smile on your face when you steer into a corner. And it puts one there again when you floor the throttle at the exit. This all-wheel-drive sedan is arguably a more entertaining car to drive than any of its rear-drive rivals. Sport sedan or not, the Audi A6 is now the car of choice in this category.

The manufacturers provided Edmunds these vehicles for the purposes of evaluation.