4000 series (Chicago "L")

The of the Chicago "L" rapid transit system consists of railcars (permanently coupled into married pairs) dating from 1981 to 2015, delivered in two series: the 2600-series and 3200-series, also known as the High Performance Family, because of innovative design and technological features from previous equipment in Chicago transit beginning with the former 2000-series cars which operated between 1964 and 1993. The third fleet of cars in the rolling stock known as the 5000-series are the newest to the Chicago "L" featuring new technologies such as exterior and interior LED signs, security cameras, new seating configuration, AC motors and new door action.

All cars are 12 ft (3.66 m) tall (from top of rail) and 48 ft 3 in (14.71 m) long (over coupler pulling faces). They are 9 ft 4 in (2.84 m) wide at the window sills but only 8 ft 8 in (2.64 m) wide at the door sills. Currently, most railcars operating on the Chicago "L" are DC power only; the 5000-series features AC motors, but the traction power supply continues to use DC.

The 4000-series cars were manufactured by the Cincinnati Car Company of Cincinnati, Ohio, between 1914 and 1924. They were the first steel cars on the Chicago "L" system. These cars were built in 2 distinct variants, with the earlier, metal-roofed cars being known as "Baldies" (due to their smooth iron roofs) and the later, wooden-roofed cars being known as "Plushies" (due to their more comfortable, green plush seats). The "Baldies" were equipped with 6 doors per car, however the center doors were never used regularly. The "Plushies" were equipped with only the end vestibule doors, but the cars internal structure was arranged to allow for the later addition of the center doors.

These cars were built as the result of several distinct purchases (dates are the date of the order, not the actual production date):

The 445 cars of the 4000-series were the last Chicago "L" cars purchased with air brakes.

When the State Street Subway opened in 1943, the older wooden cars were not allowed to operate through it for safety reasons. The only cars available to operate in the subway were the 4000-series, which eventually led to production of the 5000 and 6000-series cars.

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Wikipedia