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Gearbox: How it works and why it’s so important

The gearbox is a set of gears essential to the movement of the vehicle. These gears are made up of sprockets that, connected to each other, create the “strength” to start the gear and keep the vehicle moving. In a simpler way it can be said that it transmits the engine power, but it is not that linear.


How does the gearbox work?

The gearbox acts as a demultiplier of force coming from the engine and transmits that same force to the wheels passing through the differential. Each gearbox has within itself, usually two series of reels. The first has the name “main shaft” which brings the engine rotation depending on the clutch. The second series of reels is known as “secondary shaft” and this is where the engine rotation is transmitted to the differential. The connection between these two shafts is only possible thanks to a synchronizer and a locker The first, as the name implies, synchronizes the rotations of the two shafts as they approach with the clutch drop smoothly. The choke keeps the reels together so that the force is transmitted in full.


Types of speed boxes

There are essentially 3 types of gearboxes: automatic, semi-automatic (also known as sequential) and manual. The number of manual boxes in vehicles has been much bigger than automatic but  nowadays the opposite is happening. Each day more and more cars came out from the factory with AUTOMATIC transmission. This phenomenon is due not only to the greater reliability of today’s ATMs, but also to the lower fuel consumption of the vehicle that comes from them.


Semi-automatic gearboxes

Semi-automatic boxes are the rarest of the three types. For example, rally cars use this type of gearbox.  Here the clutch pedal is still needed, however, the gear selector has only two possible movements: forward (next speed) and backwards (previous speed to neutral).


Manual gearboxes

In the manual boxes is the driver who makes all the movement of the process of speed change when charging on the clutch and moving the gear selector and has the advantage of being the driver to make the car react manually having always control of the car.



Automatic gearboxes

This type of boxes has several sensors collecting information instantly if the car is in need of another change .The whole process is done automatically. The advantage is that it has a much more relaxed ride and does not need the clutch pedal.


What is the lifetime of a gearbox?

The gearbox are a rally durable component of a car if  is used conveniently. Although it is an element that is used frequently, the gearbox is made with durable materials, causing there to be less wear of it. In any case, every 20,000 km it is advisable to be reviewed, as well as components adjacent to it, such as: clutch  and transmission arm.

For good maintenance, you should always consider the brand’s recommendations ( oil specs and time between inspections) The usage of clutch and gear box should be taken in consideration. These two components are interconnected and, therefore, the good use of one will help to maintain the other and vice versa.

Firstly , whenever a new change is placed on any vehicle, you must have the clutch pedal at the bottom. The clutch should then be  dropped smoothly and, if acceleration is required as the clutch is released, it should be smooth. Another of the good habits to have is to put the car at the traffic light  nor jams in neutral. This reduces the pressure on the clutch cable which is one of the most fragile elements of this set.

Check out our tutorial in case you need to change gearbox oil! In this tutorial it is essential to use the oil  pump to put the new one on its clutch.

Gearbox broken symptoms

  • Loss of dismembering capacity: This indicator can be checked when you have the clutch foot at the bottom, but you cannot take away the change that is geared.
  • Skating clutch: You’ve certainly heard this expression in a mechanical workshop. This phenomenon occurs when the vehicle’s rotations increase, but the speed remains. This happens when the engine cannot transmit all the power to the wheels, because the clutch disc cannot exert enough pressure.
  • The gear lever jumps from position: This is another indicator of a gearbox malfunction. If we engage a speed, but as the vehicle is moving the change “jumps out”, it means that some of the gears in the box may be broken and it will be necessary to remove the gearbox for repair.


Gearbox price

If necessary and, depending on the brand and type, you can find a box from a few hundred euros.

Knowing how important these types of components (clutch, transmission, among others) should always be as careful when using the vehicle. Regular Inspections and maintenance is recommended regularly making sure your vehicle is always ready for any situation.

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