Two significantly similar cars, no doubt about that. Still, each one has something different to offer. Having both cars powered by diesel engines and utilizing the 4-door sedan body style within the same 'Luxury car' segment, the only major difference here really is their wheel drive configuration (rear for the BMW and 4 x 4 in the case of the Audi). The first one has a BMW-engineered powertrain under the hood, a 6-cylinder, 24-valves 231hp unit, while the other one gets its power and torque from a 6-cylinder, 24-valves 233hp engine designed by Audi.

A starting point here would be to take a look at the results from European New Car Assessment Programme (Euro NCAP) tests which were performed on both of the cars, with the Audi being a slightly better choice apparently. That aside, let's consider some other aspects which affect safety. Both vehicles belong to the luxury car segment, which is generally a very good thing safety-wise, still it doesn't help us solve our dilemma, does it? On the other hand, if we'd like to consider vehicle mass in this context too, which we definitely should, Audi A6 offers a considerable difference of 12% more metal.

Reliability is not the best thing to consider on the make level, but it is worth mentioning that both brands display similar results in faults and breakdowns, all the models observed together. That's the official data, while our visitors describe reliability of BMW with an average rating of 4.1, and models under the Audi badge with 4.2 out of 5. The same official information place 5 Series as average reliability-wise, and A6 is more or less at the same level.We should definitely mention that owners of cars with the same powertrain as 5 Series rank it on average as 5.0, while the one under the competitor's bonnet gets 4.6 out of 5.

BMW is a bit more agile, reaching 100km/h in 0.1 seconds less than its competitor. In addition to that it accelerates all the way to 250 kilometers per hour, 3km/h more than the other car. When it comes to fuel economy the winner has to be 5 Series, averaging around 6.7 liters of fuel per 100 kilometers (42 mpg), in combined cycle. We can't ignore that 19% difference compared to Audi A6.

BMW appears just a bit more reliable, although the difference is truly marginal. The most important thing when deciding between any two vehicles should always be safety, both passive and active. In my opinion, everything taken into account, Audi A6 beats the other contender by far, making it the best choice without even considering other things. From there things take a different direction, with BMW being considerably quicker, thus putting more smile on driver's face. To make things even better, it consumps less fuel! No mistake, whatever you decide here, but I'd still go for the BMW. Anyway, that's the most objective conclusion I could've came up with and it's based solely on the information found on this website. Aspects such as design, practicality, brand value and driving experience are there for you to measure them out. In case you have two minutes to spare I invite you to define your needs, desires and budget and see which car would be chosen by the virtual adviser™, among thousands of similar, yet so different vehicles.