Cars are used so often to the point where people almost fail to realise the pieces of technology are used at every instant when the car is moving, turning and preparing to stop.. For everyday purpose in vehicles, they must be able to turn efficiently, with little hassle or dispute, where only a revolutionary, small gear train allows this to happen. These are known as differentials.

But how does a differential help? Its main function is to change the speed of individual wheels. A pinion gear is attached to the power source, and has a larger ring gear, where the ring gear contains a spider gear. The small spider gear can turn by itself and with the ring gear. Within the spider gear are two side gears, each controlling a drive wheel. This is helpful especially when turning. In a straight line, the gears have the same RPM, so they can accelerate. When turning, the spider gear turns upon its own axis. This means that it can allow the side gears to turn at different speed. As they control the drive wheels, it allows them to also turn at different speed, with no skidding or stalling.

Open differentials, however, come with a significant disadvantage. They cannot deal with traction. Traction is related to the force used to generate motion. A surface with limited traction is one that is slippery, such as ice. Ice causes slipping of the car’s wheels as there is not enough resistive force to generate motion. One way to overcome this issue is through a Limited Slip Differential.

One Limited Slip Differential is a clutch-based system. Not only does it have more spider gears, but they also come in a new compartment, known as a pressure ring. The rings are placed into an outer casing, while the spider gears remain inside it. Also within the system are small pieces of machinery, known as clutch packs. They contain friction discs and steel plates, which tighten to provide a frictional force, overcoming the lack of traction in some wheels. In wheels with little traction, energy will be diverted to the wheel with more traction to get it moving again.

In family cars and vehicles, a Limited Slip Differential is enough to provide a smooth ride. However, for entertainment purposes in drifting, a newer, developed differential is used, with the spider gears firmly welded together. This means that they can rotate at the same speed. Due to the welding, it minimises the loss of energy and power otherwise loss in a Limited Slip Differential. This is ensuring both wheels always get power, so oversteering can occur.