In simple terms, the gearbox enables the driver to change the speed and move forward or backwards. Without it, you would not be able to drive your vehicle.
Since it’s introduction in 1904, the gearbox has evolved into main forms over the years but the two main transmission types are still manual or automatic. The gearbox is used heavily on a daily basis. Proper maintenance, regular servicing and changing gear in the correct manner can keep your gearbox alive and well for thousands of miles. But If you imagine how many times you change gear in a typical journey, you can understand that problems will eventually creep in.
Signs of a failing gearbox include, burning smells, knocking noises, delayed engagement when shifting gear or chrunching sounds. Gearbox issues may also trigger the check engine light.
If you need to replace your gearbox, this can be easily done at relatively low cost but it is advisable to use a qualified mechanic.