## Origins of the Automatic Transmission
The evolution of the automatic transmission began in the early 1900s with the invention of the planetary gearset. A planetary gearset consists of a sun gear, a ring gear, and a set of planet gears that rotate around the sun gear. This design allowed for a variable gear ratio, which is essential for an automatic transmission.
The first automatic transmission was patented in 1904 by Henry Ford, but it was never put into production. In 1930, General Motors introduced the first mass-produced automatic transmission, the Hydra-Matic, which was used in the Oldsmobile and Buick models. The Hydra-Matic was a three-speed transmission that used a hydraulic system to shift gears.
## Plymouth Cars and Automatic Transmissions
The first Plymouth car with an automatic transmission was the 1941 Plymouth Special DeLuxe. This transmission was a two-speed Powerflite, which was also used in other Chrysler models. The Powerflite was a vacuum-operated transmission that used a torque converter to transfer power from the engine to the transmission.
In 1954, Plymouth introduced the PowerFlite transmission, which was an improved version of the previous two-speed transmission. The PowerFlite was a three-speed transmission that used a torque converter and a hydraulic system to shift gears. The PowerFlite was used in Plymouth cars until 1965, when it was replaced by the Torqueflite transmission.
The Torqueflite transmission was a four-speed transmission that used a torque converter and a hydraulic system to shift gears. The Torqueflite was used in Plymouth cars until 1977, when it was replaced by the A-904 transmission.
The A-904 transmission was a three-speed transmission that used a torque converter and a hydraulic system to shift gears. The A-904 was used in Plymouth cars until 1988, when it was replaced by the A-604 transmission.
The A-604 transmission was a four-speed transmission that used a torque converter and a hydraulic system to shift gears. The A-604 was used in Plymouth cars until 1994, when it was replaced by the 42LE transmission.
The 42LE transmission was a four-speed transmission that used a torque converter and an electronic system to shift gears. The 42LE was used in Plymouth cars until 2000, when it was replaced by the 41TE transmission.
The 41TE transmission was a four-speed transmission that used a torque converter and an electronic system to shift gears. The 41TE was used in Plymouth cars until 2001, when it was replaced by the 545RFE transmission.
The 545RFE transmission was a five-speed transmission that used a torque converter and an electronic system to shift gears. The 545RFE was used in Plymouth cars until 2007, when the Plymouth brand was discontinued.
## Conclusion
Plymouth cars were equipped with a variety of automatic transmissions over the years, from the two-speed Powerflite to the five-speed 545RFE. The automatic transmission has become an essential feature of modern vehicles, and Plymouth cars were at the forefront of this automotive technology.