While cleaning out his late father’s garage, a man and his friend discovered a dusty 1980s sedan. The gear selector looked familiar—P, R, N, and D—but one strange letter stood out: “E.” They guessed it meant Electric or Emergency. Instead, they discovered a forgotten piece of automotive history: E stood for Economy. The feature emerged after the 1970s oil crises, when automakers were searching for ways to reduce fuel consumption. Selecting E changed the transmission’s behavior, encouraging earlier shifts and lower engine RPMs. The result was better fuel economy and smoother cruising, but there was a trade-off: acceleration could feel noticeably slower. In many ways, it was an early mechanical version of today’s Eco Mode.

By the late 1980s, however, the mysterious gear began disappearing. Automatic transmissions were becoming increasingly sophisticated, with electronic controls and onboard computers capable of adjusting shift patterns automatically. Overdrive became more common, fuel injection improved efficiency, and the car’s computer gradually took over the job that drivers once controlled with a simple letter on the shifter.

The interesting part? The idea never disappeared—it simply went digital. Modern Eco modes can adjust throttle response, shift timing, and other settings with the push of a button. That little “E” is a fascinating reminder of how engineers once tackled fuel efficiency with simple mechanical solutions. A forgotten letter on an old gear selector was actually an early glimpse of the fuel-saving technology we use today.