Brendan McAleer
January 6, 2015

The automatic transmission may seem like witchcraft to some, but here’s how it became so ubiquitous in today’s cars

Basically, we’re talking witchcraft. When it comes to the modern automobile, even the casual observer can relate how most systems work: gas goes boom – the engine turns; brakes clamp down – the car comes to a stop; turn the steering – front wheels pivot. But as for the device marked PRND? That thing’s gotta be made in Hogwarts.

Science fiction writer Arthur C. Clarke once famously observed, “Any sufficiently advanced technology is indistinguishable from magic.” But if it’s magic, why are most enthusiasts so quick to deride the modern automatic transmission? After all, it’s far and away the most popular choice and opens up whole new worlds of driving. It’s easier to live with in stop-and-go traffic, you can enjoy your coffee without having to scrabble for the shifter, and it surely holds particular appeal to members of the buccaneer community. Arr, it be quite taxin’ te operate a clutch with me peg leg, Jim lad.

Leaving aside automated manuals such as Porsche’s PDK, and pulley-based systems like the continuously variable transmission (CVT), here’s a brief overview of the history of the modern auto-box. Wands at the ready, Potters and Grangers, let’s begin.

Slushy beginnings

Just who came up with the first automatic transmission is as muddled a tale as who invented the automobile (and don’t necessarily believe claims that Mercedes-Benz did the latter). At the turn of the century, all kinds of inventors were fiddling around with unusual ways to get their horseless carriages to trot at different speeds.

Frenchmen Louis-Rene Panhard and Emile Levassor must be awarded the distinction of coming up with the first proper transmission, demonstrated in 1894. And by “demonstrated,” I mean, “it broke.” The theory was there, and the demo car was soon working again, but it rather ignominiously gave up the ghost before the assembled press corps, and Panhard and Levassor were reduced to lecturing in front of a chalkboard. “More hocus-pocus from charlatans!” the papers cried.

Next, the Sturtevant brothers of Boston, Mass., managed to work out a two-speed automatic transmission based on centrifugal weights. Essentially, this relied on the speed of the engine to activate a series of weights, that, um, would deactivate a clutch and … OK, look: even after reading up on this thing, I have no idea how it works, except to say that it mostly didn’t. It too broke down with sad regularity, bringing a literal interpretation to the shiftless transmission.

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