The vacuum pump is a fundamental mechanical device for the correct functioning of the braking system of any vehicle equipped with a brake booster. The best-known application of vacuum pumps is that which serves to create the depression necessary for the brake booster to which the brake pump is directly connected to function correctly.
There are various vacuum pump models on the market, such as the old membrane pumps, generally driven by a pulley and pulled by the service belt, palette pumps, which are rotated directly by the engine and lubricated by oil coming from the engine itself, or the latest tandem pumps, so called because they are composed of two separate chambers, one of which provides the vacuum for the brake booster, the other taking care of pressurising the diesel fuel. For this type of pump too, lubrication comes from the oil coming from the engine that powers it directly.
A further category, the most recent and most advanced, is made up of modern electric vacuum pumps, which are powered by an electric motor which sets them in rotation, thus causing depression.