Transmission
The transmission is a device that is connected to the back of the engine which sends power from the engine to drive the wheels. Its primary job is to allow the engine to operate while providing a range of output speeds. The transmission contains planetary gearsets which are in charge of providing different gear ratios; without one, vehicles would be limited to a one gear ratio, wearing out the vehicle quickly; making it nearly undriveable. In addition to the various forward gears, the transmission also has a neutral and park position which disconnects the engine from the drive wheels, allowing the wheels to turn in the opposite direction and back up.
What can go wrong?
Throughout wear and tear, the transmission's fluid may begin to leak and serious damage can occur. If the fluid becomes cloudy or muddy, it may be contaminated. If you drive a standard vehicle, the clutch can jam which locks the solenoid (the device that controls how the fluid travels), preventing the fluid from contacting the torque converter, which will result in severe damage.
What can you do?
Watch for leaks or stains underneath your vehicle. If you see a persistent red oil leak, check with a service advisor immediately before more damage occurs. Check the fluid for colour or odor; if the fluid is cloudy, muddy or has a burned odor, it should have a transmission drain and refill by a service technician. Lastly, always follow the proper maintenance schedule provided by your owner's manual or suggested by your service advisor to avoid major damage and costly repairs.