What is a Gearbox?

What would a car be like if it didn’t have gears? Starting a car off the mark would be laboriously slow, noisy and uncomfortable. There would also be a tremendous strain on the engine and driving parts of the motor vehicle. Having a car with a gearbox is a much better solution. In order to get smooth starts and to have power to pass slower moving traffic and climb hills, a gearbox with a variety of gear ratios must be installed at some point between the engine and the driving wheels of the motor vehicle. The gearbox provides ratios that will multiply the torque of the engine.

A gearbox takes the power developed from the engine and uses a series of gears to give a car more power and less speed, or less power and greater speed. A reduced output shaft speed multiplies the input torque.

Another term for a gearbox is transmission. The use of the term transmission is common, but is generally kept for describing the automatic gearbox as an automatic transmission.

Gearboxes have moved from being one speed to three speed, four speed and, more recently, five speed gear boxes. Currently, gearboxes are being produced with six forward gears; however Lexus is now making some of their models with an eight speed gearbox.

Manual gearboxes (gearboxes that are put through the gears manually by the driver) need to be driven smoothly to avoid the bunny hops or stalling at the lights. Perhaps this is why many ladies (like this writer) prefer to drive an automatic!

We hope that helps answer the question ‘What is What is a Gearbox?’!

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