Audi: four joined circles
BMW: one circle divided into 3 equal sections, each 60-degrees
Mercedes: a circle quartered
Toyota: Nested ovals
Mitsubishi: Diamonds at 60-degrees
Chevy: A square and a parallelogram
Volkwagon: A stylized VW with classic 30/60 angles.
Ford: A single oval
Renault: Parallelograms that look like a 3D object
If you look back in history, even more care logos bore the hallmarks of Art Deco.
So, why don't we perceive these logos as Art Deco? I think the main reason is that we're used to them, and we associate cars with them, not Art Deco, so we just don't see them that way. A second reason is that an Art Deco element are not Art Deco. It takes more than geometric angles and drafting tricks to make Art Deco. These elements by themselves can look pleasing, which is why people use them, but without the context to back them up, they're just pleasing shapes.
I'm also somewhat befuddled why rims aren't Art Deco. I think it's because the rims themselves don't attempt to redefine or break up their circle, and like the logos, exist without enough context. If the entire car were to scream Art Deco, then the tires would be integral to that feel, but the cars don't.
Grills represent the final place where Art Deco and automobiles meet. The grill work is rather strong by itself, and most designers seek to reduce its impact by breaking it up somehow. This requirement uses many of the same techniques as Art Deco, with very similar results.
A brief review of Art Deco cars reveals why Art Deco and cars met with limited success. While Art Deco styled automobiles were sunningly beautiful, they were also kinda stupid looking. The practical requirements of the vehicle truly fought with the aesthetics of the design. The result was a narrow category that the public didn't flock towards, mostly because of cost, but also because of looks. If the demand had been there, designers would have met it.
Return to: Art Deco 101
Douglas Milewski is a fantasy writer who liked drafting class too much. In his recent artistic struggles to produce art deco for his own covers, he found no internet sites dedicated to the technical underpinnings of the art. Seeing a niche that needed filling, he has documented his hard learned experiences. He doesn't claim that he's right, and would very much appreciate it if someone more competent would save him from his own folly.