ATF oil

read about transmission oils here:
volkswagen transmission oil specifications

automatic transmission oil or atf.
the vast majority of gearboxes in passenger cars and light trucks work automatically, that is, there is no need to change gears manually. automatic transmission fluid atf is an important component of any automatic transmission. The most important parameters of automatic transmission oil are as follows:

heat resistance and thermal stability, helps to prevent the formation of precipitation and deposits as a result of high temperature operation of the gearbox.
friction characteristics allow for smooth gear changes by ensuring proper friction on gearbox clutches and belts
extreme pressure/load carrying capacity ensures anti-wear and gear durability
viscosity stability helps maintain viscosity or the correct fluid thickness over a wide temperature range
low temperature flow ensures efficient operation of hydraulic and electronic controls at low temperatures in winter.

what type of atf fluid do i need?
depending on the make, model type and model year of your vehicle, a special automatic transmission fluid is required to ensure proper transmission performance and protection. always follow the vehicle manufacturer's recommendations to ensure the correct fluid is used and the fluid change interval is followed. this recommendation can usually be found in your vehicle's owner's manual.

types of automatic transmission fluids are divided into several categories:
1) ford, gm and chrysler atf specifications:
atf fluids are not defined by weight, as motor oil is. rather, it is defined by a specification, certification, or application.

ford, gm and chrysler have established their own specifications for automatic transmission fluids. for gm it is the dexron spec series with the main spec being dexron vi for newer gm vehicles. earlier dexron specs would be acceptable for older gm vehicles. for ford, mercon spec is important, latest is mercon lv. for chrysler the atf +4 spec is the latest spec.

2) universal automatic transmission fluids, i.e. multi-vehicle transmissions atf
These transmission fluids have become popular and may be certified by GM, Ford, and Chrysler, but are also suitable for use in Japanese and European vehicles.

3) continuously variable transmissions (cvts)
The use of cvts to improve fuel economy is increasing. such transmissions are common on hybrid vehicles, but can also be found on non-hybrids. unlike classic automatic transmissions, also known as stepless transmissions, cvt transmissions have continuously variable speeds with different gear ratios. cvt fluid should be used in such a transmission for proper performance and protection, especially for wear protection on the cvt push belt.

4) type f transmission fluid
this fluid meets old ford specs and is not recommended for modern transmissions. it can be a fluid for Ford's older classic cars, racing or hydraulic applications.

atf oil change - correct service intervals
the correct time to change the automatic transmission fluid is determined in the individual user manuals. in many cases, fluid change interval requirements are more frequent when the vehicle is operated in severe conditions. such conditions are determined by the manufacturer.