Out of all the German automotive brands, Volkswagen has to be the most well-known. It's made a name for itself producing solid, reliable, everyday cars for decades. That reputation started all the way back to when the first of the classic Beetles rolled off the production line after World War II. If that reputation is so good, why try to change it? Well, Volkswagen clearly didn't get the memo. As the new millennium emerged, Volkswagen decided to do the most positively un-Volkswagen thing it could think of. Volkswagen Once Tried To Build A Car Nobody Expected It To CarBuzz If you think of Volkswagen, you aren't going to think of a luxury car. It's pretty antithetical to the company's name in the first place. Volkswagen is German for "people's car", after all. But, Volkswagen did what nobody expected it would ever do, and actually built one. This luxury Volkswagen first appeared back in the early 2000s, during a time that some consider to be a golden age of automotive engineering. It was special, innovative, and paved the way for how the Volkswagen Group would develop its more luxurious products. It Was The Result Of Ferdinand Piëch's Unique Vision For The Volkswagen Group Why did Volkswagen decide to build a luxury car? That was because of a directive from its eccentric boss at the time. The VW Group was well in the throes of the Ferdinand Piëch era, and this man had a unique vision for what he wanted the company to be.Piëch loved big projects and crazy engines. As a result, we got some of the most insane creations the Volkswagen Group had ever made. The Bugatti Veyron, for example, was created at Piëch's insistence. So was the car we're about to discuss, and its siblings that bore the badge of one of Britain's most beloved automotive brands. The Volkswagen Phaeton W12 Was A Bentley In Volkswagen Clothes Bring A TrailerWhat was this crazy, innovative luxury car that Volkswagen ended up making? Well, it was the Volkswagen Phaeton. It was the longest-wheelbase car in the Volkswagen Group's entire lineup at the time, and it was also one of the most opulent. It came with multiple engine options, but the one that made the most headlines was the W12.This was a development of the engine that was used in the Nardo supercar, and it's perhaps one of the craziest production engines ever made. It's essentially two 3-liter VR6 engines, bolted together in a W formation. The result is a big-displacement engine that's actually surprisingly compact. It also produces big power for a luxury car from the 2000s—420 brake horsepower and 406 pound-feet of torque in the initial versions. That increased to 444 bhp and 413 lb-ft of torque from 2004.Bring a Trailer A huge factor into how the Phaeton actually happened is that, under the skin, it's actually not very Volkswagen at all. It actually has much more in common with the Bentley Continental GT and the Bentley Flying Spur. It shares a platform with both those cars, and the W12 engine is almost exactly the same as the one in the Bentleys. The only difference is that the VW Phaeton's W12 doesn't have the twin turbochargers.The biggest trump card the Phaeton had over everything else that was sold in its class at the time was how gloriously over-engineered it was. That was thanks to Ferdinand Piëch having some seriously demanding engineering requirements for it. This included the ability for it to be able to cruise at 300 km/h (186 mph) in temperatures of near 50 degrees Celsius or 120 degrees Fahrenhei. The Phaeton was an early adopter of adaptive air suspension, as well as 4-zone climate control. It also had double-glazed windows, extensively used aluminum in its construction and a huge amount of safety features that we take for granted in today's premium cars, including radar cruise control. Combine that with the incredible engineering of the W12 engine in and of itself, and there really wasn't anything like this on the market. It Was Also Available With Volkswagen's V10 Diesel Bring a Trailer The 6-liter W12 wasn't the only crazy engine you could have in the Volkswagen Phaeton. If you lived outside of America, you could have this car with the ridiculous 5-liter V10 diesel engine. This pre-dieselgate monster produces a seemingly underwhelming 310 hp. But, it also produces 553 lb-ft of torque. That was a monstrous figure back in its day. That economy bonus you'd get from this huge diesel over the W12 petrol engine definitely made it a better option for anyone who wanted serious luxury car performance, but also needed to do a lot of highway miles. It Wasn't The Only VW Group Sleeper To Get The W12 Engine The Phaeton has to be the most famous VW Group sleeper car to get the W12 engine. It wasn't the only one, though. One other Volkswagen model and one Audi model got the naturally aspirated version of the W12 that the Phaeton used. Those were the Audi A8L W12 and the Volkswagen Touareg. The Audi A8L W12, best known by many as Jason Statham's car of choice in Transporter 2, was supposed to be a hyper-luxurious halo model that could challenge the V12-powered Mercedes S-Class and BMW 7 Series models of the time. Meanwhile, the Volkswagen Touareg R50 was an attempt at a performance SUV by VW.The Touareg W12 didn't last long. It was dropped after the first generation of the car. The Audi A8 got the W12 as an engine option for a long time. The last generation of the A8 to get the W12 was the D4, which went out of production in 2016. This was 15 years after it was first introduced as an engine option, right at the end of the run of the original D2 generation. It Was An Incredibly Impressive Luxury Car - But Nobody Wanted It VolkswagenThe Volkswagen Phaeton genuinely was very impressive for its day. Those advanced features and that incredible over-engineering really added up to an excellent car. But, when it came to actually trying to sell it, the Phaeton was a total failure. Sales were never anywhere near as good as its rivals, which were perceived as being more upmarket. That's mainly thanks to good old European badge snobbery, barely anyone wanted to drive around in a big luxury car that had a VW badge on the front. Why It's Such A Tempting Used Buy Bring a TrailerThanks to how unloved the Phaeton was during its day, it's become one of the biggest luxury bargains out there. The average used value for the Phaeton across all its variants is $11,292. When you specifically look at the W12 models, those values become even more bargain-basement for what you're getting. It's not unusual for Phaeton W12s to sell for as little as $9,700. If you've ever wanted one of these cars, now really could be the best time to take a punt on it. Buying One Still Takes A Lot Of Courage CarBuzzWhile the Phaeton W12 offers a great luxury bargain on the used market, it's still a very brave choice to buy one. Anyone who's thinking that these can be serviced anywhere where you can service a regular Volkswagen will be in for a real shock when it's time to get that sorted.Due to their unique nature, Phaetons can only be serviced at certain garages that are specially trained and outfitted to work on them. That can mean that servicing costs become expensive, even in luxury car terms. Owners have talked about having to spend over $5,000 on repairs for their cars at points. Finding spare parts for these cars can also be an absolute nightmare, and all those complicated systems mean that problems can keep piling up and up with age. Other Crazy Production Cars Volkswagen Made Volkswagen We've already talked about the Audi A8L W12 and the Volkswagen Touareg R50 as examples of other crazy sleepers the Volkswagen Group unleashed onto the world. But, were there any other out there during the Piëch era? Absolutely. If you really know your stuff about Volkswagens, you may have already heard about them. If you haven't, be prepared to hear about some positively crazy cars that no manufacturer would dare to put out today. Volkswagen Touareg V10 TDI Bring a TrailerAgain, the Volkswagen Touareg had the W12 engine as an option. It also got the V10 diesel, with all its glorious torque. This was actually marketed by Volkswagen as a big selling point for the car at the time, doing all sorts of stunts that took advantage of its monstrous pulling power. This included towing an entire Boeing 747. Unfortunately, Dieselgate marked the end of this quietly brilliant luxury SUV. Volkswagen Passat W8 4MOTION Bring a TrailerThe W12 wasn't the only 'W' engine Volkswagen brought into production. It also developed a 4-liter W8 engine, which it put into the Passat W8 4MOTION. This was a genuinely fantastic sleeper, with enough power to compete with some serious performance sedans of its day. It also could be ordered as an estate, and you could have it with an old-school 6-speed manual transmission. Like the Phaeton W12, these cars were unloved in their day. But, with a bit more enthusiast appreciation, they could become genuine performance classics.Sources: Audi, Bring A Trailer, Classic.com, Volkswagen, VWvortex.com