You’ll find an excellent survey of suspension design circa 1939 in this original Oldsmobile film. This is how they went down the road in ’39—watch.
The Oldsmobile division of General Motors was an early adopter of coil-spring suspension at all four wheels, which the automaker called QuadriCoil Springing. To promote the development Olds produced this 1939 film, which details the history of automotive suspension starting with the Curved-Dash Olds of 1903—complete with a charming historic reenactment. Then follows a thorough description of the Oldsmobile chassis for 1939, including a comparison of leaf vs. coil springs and their relative pros and cons. While presented in layman’s terms, the info is sound and interesting.
Several items worth noting about the ’39 Olds chassis today: First, the short-long-arm (SLA) independent front suspension, in which the lever arm of the hydraulic shock absorber doubles as the upper control arm. This basic layout served GM well in all sorts of passenger vehicles for many years.
Next, the rear suspension employs a pair of long, diagonal trailing arms fixed at the rear axle with a Panhard bar for lateral control. This same configuration would be reintroduced by GM on the 1960 Chevrolet pickup, and is now immortalized as the familiar “truck arm” rear suspension used throughout NASCAR for many decades now. As they say, there’s little new under the sun, especially in the automotive world. Enjoy the video.