In the 1980s and 1990s, certain cars featured a mysterious letter “E” on or near the gear shifter. Standing for “Economy” or “Efficiency,” this feature arose from the 1970s oil crises, giving drivers a deliberate choice to trade raw speed for better fuel conservation.

On older automatic transmissions, engaging “E” mode altered the car’s hydraulic programming to keep RPMs low. The vehicle would shift into higher gears much earlier, resist fuel-heavy downshifts during acceleration, and often start moving in second gear for a smoother, quieter ride.

On manual cars, like classic Volkswagens, “E” served as an extra-tall overdrive gear for highway cruising. Shifting into “E” caused engine RPMs to plummet and silenced the cabin, though the gear lacked acceleration power and required shifting back down to pass other vehicles or climb hills.

The physical “E” eventually vanished as car technology advanced. Today, sophisticated engine computers and multi-gear transmissions manage fuel efficiency automatically, transforming the tactile, mechanical “E” switch of the past into the digital “Eco Mode” buttons found on modern dashboards.