Why, after changing the oil in the automatic transmission, the box may start to twitch

After replacing the lubricant in the gearbox, some drivers notice deterioration in its operation - there is no former smoothness of switching, kicks appear. The AvtoVzglyad portal found out what causes such a strange phenomenon.

The oil in an automatic transmission, as well as in the engine and any other vehicle component that requires lubrication, tends to be produced. It just gets dirty. The reason for this is frictional dust and soot, wear of metal transmission elements, Teflon rings, gears and other things. Yes, a filter is provided here to clean the oil, and even magnets that collect steel chips. But very small debris still remains in the oil and continues to circulate in the system.

As a result, all this leads to a deterioration in the lubricating, cleaning and cooling properties of the oil. Add here overheating, driver temperament, operating conditions. If all this is far from ideal, then nothing good can be expected for an automatic box without an oil change. She can drive off to her boxed paradise for both 30 and 000 km of run. In other words, it is necessary to change the oil, and this must be done depending on the intensity of the car's operation.

But why, after changing the oil, some drivers notice a deterioration in the operation of an automatic transmission?

The new oil has a number of additives, among which there are those that are responsible for washing and cleaning the box. That network, if you fill in fresh grease in the automatic transmission, and even in one in which oil splashes from the factory, then, of course, it begins its work with cleaning. The deposits accumulated over the years and kilometers begin to fall off and be cleaned out. And then they go straight to the valve body, where the valves are located, which immediately react to this by wedging - dirt simply clogs a gap of several microns in the channel. As a result, the operation of pressure regulators may be disturbed.

Also, dirt can clog the protective mesh of the electric valve. And here you should not expect anything good. It’s just impossible to predict how the situation will develop after an oil change. Therefore, many recommend changing the oil partially - they drained a little, added the same amount of new oil. As a result, the box is cleaned, but not so extreme if you change the oil immediately and completely.

A box with old oil, viscous from dirt, can still work on it, but the wear of its elements develops rapidly - for example, gaps increase. At the same time, the pressure inside the system may still be sufficient - dirty oil is quite dense, and it fills the broken gaps properly. But if you pour new oil into the automatic transmission, then problems will begin with pressure. And, therefore, we will see the failure of the unit to work. In other words, if you have never changed the oil in the “machine”, then before doing this, pay attention to the condition, consistency and color of the old oil. If they leave much to be desired, then by changing the lubricant you will only exacerbate the accumulated problems.

The conclusion suggests itself: if you want the automatic transmission to serve you for a long time, then, firstly, you should not scoff at the box - you don’t need sharp starts, slips, jams, buildups, overheating. Secondly, make it a rule to change the oil periodically, as you do with the oil in the engine. An interval of 30-60 thousand kilometers is quite adequate.