drive train

Anselma Drive Train. circa 1747

Pictured: Portion of the drive train at the Mill at Anselma, a.k.a. Lightfoot Mill, circa 1747, in commercial operation until 1982. Chester Springs, Pennsylvania, USA.


Single-speed. Coaster brake. Front hand-brake. Fender. Drive-train detail

Car drive train

Transmission – the gearbox that uses gears and gear trains to provide speed and torque conversions from a rotating power source to another device. The transmission adapts the output of the internal combustion engine to the drive wheels. Engines need to operate at a relatively high rotational speed, which is inappropriate for starting, stopping, and slower travel. The transmission reduces the higher engine speed to the slower wheel speed, increasing torque in the process.

Transmission or gearbox – gears working together. The engine turns the crankshaft. The crankshaft turns the transmission’s gears which make the wheels spin. But the wheels do not spin as fast as the engine makes the crankshaft spin. The gears provide more force (more torque), so the wheels can make the entire car move.

  • manual – the driver to decide when to shift gears. Manual transmission is also called standard transmission.
  • automatic – shifts between gears by itself (except reverse gear, and a parking gear).


  • Axles – structural component of a wheeled vehicle. The axles maintain the position of the wheels relative to each other and to the vehicle body. As the wheels are the only part touching the ground, the axles must bear the weight of the vehicle plus any cargo.
  • Four-wheel drive (4WD) – a feature on a vehicle that allows all four of the wheels to operate. 4WD is built differently depending on the manufacturer and has a number of pros and cons associated with it, including its ability to manage different surface conditions and its inability to provide sufficient torque in circumstances when one wheel leaves the ground.
  • all wheel drive (AWD) – is only in operation on a part-time basis when torque (the force required to move the vehicle) needs to be applied to all of the wheels to supply the right amount of traction in conditions where two wheels will not suffice.

That’s engineering

  • bearings – The supports for rotating mechanical parts such as axles and wheels. They should have as little friction as possible so the axles or wheels can turn easily.
  • friction – the resistance between two surfaces as they move against each other. For example, the friction between the soles of your shoes and the floor is what prevents you from slipping and falling down.

Engineering ideas

  • gear, torque, power, rotation, axle,