M15

Hans Nibel had succeeded Ferdinand Porsche as technical director at the start of 1929, and the car he unveiled at the Paris Salon in October 1931 is generally reckoned his most important design. The Typ 170 was the first Mercedes with independent suspension at all four wheels — transverse leaf springs and wishbone-like linkage at the front, a two-joint swing axle at the rear — and, by the company's account, the first passenger car anywhere built in real numbers that way. Its 1.7-liter six was small enough to be cheap to tax and smooth enough to justify the cylinder count.

At 4,400 reichsmarks the four-door saloon undercut the cheapest Typ Stuttgart by nearly 1,600, and came with hydraulically operated drum brakes on all four wheels, central chassis lubrication and a combined ignition and steering lock. Daimler-Benz built 4,438 of them in 1932 alone — more than its entire passenger-car output of the year before. Looking back, chairman Wilhelm Kissel credited the company's survival to two things: the quality of the swing-axle car and the merits of the diesel. In all 13,775 were built before the four-cylinder 170 V replaced it in 1936.