What Exactly Does An Automatic Transmission Fluid Do?

The automatic transmission fluid is one of the most important fluids for your car; here are some of its essential functions:

Cooling the Transmission System

The transmission system generates considerable heat; some of the heat comes from the engine (combustion) while some of the heat comes from the movement/friction of the different parts of the system. Unfortunately, most parts of your car, including the transmission system, aren't designed to operate under extreme temperatures. Therefore, there must be a way to get rid of the heat before it causes damage, and the transmission fluid provides it by carting away the generated heat.

Lubricating Transmission Parts

Most of the transmission parts perform their functions via movement. The different components of the transmission include the gears, the torque converter, and the hydraulic controls, among others. The sluggish movements of these parts will result in inefficient transmission performance. The transmission fluid provides the viscosity necessary for all these parts to undertake their movements without sluggishness, thereby ensuring your transmission system's efficiency. 

Providing Hydraulic Power

Hydraulic power is the power transmitted by fluid movement, which is then converted into mechanical power. The transmission fluid provides hydraulic power in the transmission system by transferring power to the relevant areas such as the gears and the linkages. Every time you manipulate the transmission system, for example, when changing gears, you instigate a chain reaction that ends up with the transmission fluid transferring power from one point of the system to another.

Protecting Transmission Surfaces

Lastly, the transmission fluid is also there to protect the surfaces of the different components of the transmission system. The transmission fluid is able to do this because it forms a thin layer of fluid between different parts in contact so that they aren't technically in contact. That way the rate of wear and tear is reduced and the life of your transmission system is extended.

Dangers of Contaminated or Inadequate Transmission Fluid

As you can see, the transmission fluid is very important and your car can suffer serious effects if you are operating it with degraded or inadequate (leaking) transmission fluid. Here are some of these effects:

  • Erratic shifting of gears
  • Difficulty shifting gears
  • Unexpected surging of the car
  • Delays in shifting
  • Clutch lockup
  • Transmission damage – in the long run

A short drive, say to the auto repair shop, a small amount of leaking or degraded fluid is permissible. However, you should not continue driving as usual if you have transmission fluid problems because it may damage the transmission system in the long run.