Air Conditioning in Cars

The first car with an actual refrigeration system was the 1940 model year Packard.

Fender

In 1901, Frederick Simms invented the first car fender. Similar to the railway engine buffers of the period.

Power Steering

Francis W. Davis invented power steering. In the 1920s, Davis was the chief engineer of the truck division of the Pierce Arrow Motor Car Company, and he saw first hand how hard it was to steer heavy vehicles. Davis quit his job and rented a small engineering shop in Waltham, MA. He developed a hydraulic power steering system that led to power steering. Power steering became commercially available by 1951

Supercharger

Ferdinand Porsche invented the first supercharged Mercedes-Benz SS & SSK sports cars in Stuttgart, Germany in 1923.

Third Brake Light

In 1974, psychologist John Voevodsky invented the third brake light, a brake light that is mounted in the base of rear windshields. When drivers press their brakes, a triangle of light will warn following drivers to slow down.

Transmissions

In 1832, W. H. James invented a rudimentary three-speed transmission. Panhard and Levassor are credited with the invention of the modern transmission - installed in their 1895 Panhard. On April 28, 1908, Leonard Dyer obtained one of the earliest patents for an automobile transmission.

Turn Signals

Buick introduced the first electric turn signals in 1938.

Source: about.com

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