The proper vehicle operation is ensured by five main fluids that require periodic replacement: engine oil, transmission oil (gearbox oil), antifreeze, power steering fluid, brake fluid. The automobile makers recommend the following replacement intervals: for engine oil - 7-10 thousand operational km, oil in automatic transmission and manual transmission - 50-60 thousand operational km, replacement of antifreeze - annually, replacement of brake fluid - 30-40 thousand km, oil change in axles - 30 thousand km. However, it is not always possible to maintain such intervals, therefore, for example, it is required to replace the brake fluid, if the brake pedal goes to the floor when pressed, the fluid has changed its color, and the fluid level has decreased. It is required to replace antifreeze, if the liquid has changed its color, sediment has appeared in the expansion tank, and an indicator strip shows a change in the properties of antifreeze. Plus, fluids are replaced upon completion of operations in units that use these fluids in their operation.