The main function of filters is to protect engines and other machineries against dust and dirt which enters in the mechanical equipment mixed with oil, air, fuel and hydraulic fluids.

Improper vehicle maintenance and inadequate use of filters can dramatically shorten the life of an engine.

Knowing the filtration process and the various types of filters contributes to extend engine life and reduce the risk of failure.

Classification of filters according to the fluid to be filtered:

• Air filters
• Engine oil filters
• Hydraulic oil filters
• Fuel filters: gasoline, diesel and gas

Air filters: retain existing abrasive particles in the environment air sucked thus preventing the engine, mainly piston rings and cylinders wear prematurely. Importantly, this filter is considered one of the most important, because the fluid that seeps comes from uncontrolled by users such as the air traffic routes or workplaces of the drive means.

Oil filters: isolate existing abrasive particles in the oil causing engine wear, preventing the dirt to concentrate on a detrimental degree. Thus contribute to lasting longer engine and oil can be used longer. With this filter rods and crankshaft shells mainly is protected.

Fuel filters: are indispensable for diesel engines, which injection sensitive elements must be protected against impurities in the fuel. They also provide effective protection against dirt in the carburetor and injectors in gasoline engines and therefore also against motor failures caused by it.