Transmission
A metal-housed gear system that transfers power from the engine to the driveshaft or axles, adjusting speed and torque ratios.
The transmission is a core drivetrain component that acts as the gearbox of the vehicle. Its primary role is to transfer power from the engine's crankshaft to the driveshaft or drive axles, using a set of gears of different sizes to match the engine's speed and torque output with the driving speed.
There are three main types of transmissions: manual transmissions, which require the driver to use a clutch pedal and gear shifter; automatic transmissions, which use hydraulic pressure and a torque converter to shift gears automatically; and continuously variable transmissions (CVTs), which use a system of belts and pulleys to provide an infinite range of gear ratios without distinct gear changes.
Transmissions operate under high heat and pressure, relying on transmission fluid for lubrication, cooling, and (in automatics) hydraulic pressure. Over time, this fluid breaks down or becomes contaminated with metal shavings, which can lead to slipping gears or internal damage. Regular fluid flushes or exchanges are key maintenance steps.
Common signs of transmission issues include slipping out of gear, delayed response when shifting, harsh or clunking gear changes, transmission fluid leaks (which is typically a red or pink fluid), and whining or buzzing noises. A malfunctioning transmission requires immediate professional attention to avoid complete drivetrain failure.