Early automobiles used sliding-mesh manual transmissions with up to three forward gear ratios. Since the 1950s, constant-mesh manual transmissions have become increasingly commonplace and the number of forward ratios has increased to 5-speed and 6-speed manual transmissions for current vehicles. In a sincronizada with a manual transmission, the flywheel is attached to the engine’s crankshaft, therefore rotating at engine speed.

The design of most manual transmissions for cars is that gear ratios are selected by locking selected gear pairs to the output shaft inside the transmission. Contemporary manual transmissions for cars typically use five or six forward gears ratios and one reverse gear, however, transmissions with between two and seven gears have been produced at times. Operation of a constant-mesh 4-speed manual transmission. Many of the first automobiles were rear-engined, with a simple belt-drive functioning as a single-speed transmission. The 1891 Panhard et Levassor is considered a significant advance in automotive transmissions since it used a three-speed manual transmission.

Top and side view of a typical manual transmission, in this case, a Ford Toploader, used in vehicles with external floor shifters. The first car to use a manual transmission with synchromesh was the 1929 Cadillac, however most cars continued to use non-synchronous transmissions until at least the 1950s. Up until the late 1970s, most transmissions had three or four forward gear ratios, although five-speed manual transmissions were occasionally used in sports cars such as the 1948 Ferrari 166 Inter and the 1953 Alfa Romeo 1900 Super Sprint. Six-speed manual transmissions started to emerge in high-performance vehicles in the early 1990s, such as the 1990 BMW 850i and the 1992 Ferrari 456. The first 6-speed manual transmission was introduced in the 1967 Alfa Romeo 33 Stradale.

Western Europe were equipped with manual transmission, versus 16. A manual transmission has several shafts with various gears and other components attached to them. The input shaft is connected to the engine and spins at engine speed whenever the clutch is engaged. The countershaft has gears of various sizes, which are permanently meshed with the corresponding gear on the input shaft. The fixed and free gears can be mounted on either the input or output shaft or both.

For example, a five-speed transmission might have the first-to-second selectors on the countershaft, but the third-to-fourth selector and the fifth selector on the main shaft. This means that when the vehicle is stopped and idling in neutral with the clutch engaged and the input shaft spinning, the third-, fourth-, and fifth-gear pairs do not rotate. When neutral is selected, none of the gears on the output shaft are locked to the shaft, allowing the input and output shafts to rotate independently. For reverse gear, an idler gear is used to reverse the direction in which the output shaft rotates.