Modern ATF is a mixture of highly refined components, each designed to add its specific property to the mix. I would say that of all the chemicals used in an automobile, the automatic transmission fluid is the most complex.
Most companies are highly reluctant to share their "proprietary" compositions, as evidenced by these SDS's.
https://www.grovesindustrial.com/msds/ILU_TRANS.pdfhttps://www.onboces.org/cms/lib/NY02216875/Centricity/Shared/MSDS%20K_List/Kendall%20Dexron%20Mercon%20ATF.pdfThey either don't tell you what's in it, or basically do a "data dump" of every possible oil it COULD be so as to avoid listing what is actually in it. Really helpful to say a poison control center, don't you think? Though, when you've read as many SDS's as I have, you see trends and learn characteristics, and can whittle down the probable list of suspects.
AMSOIL's synthetic ATF looks like it has some serious silicones in there.
https://www.amsoil.com/msds/atf.pdfThis last one, a licensed Dexron 3 type, sheds some light on what we're after.
https://www.tetconnect.com/images/stories/virtuemart/documents/XPF001_SDS.pdfThough not listing the main carrier oil, it lists a light naphthenic mixture (very good solvency and oxidation resistance) with DMSO (a penetrant), as well as an alcohol and toluene (solvents). The DMSO component is intriguing.
DMSO (dimethylsulfoxide) is a by-product of the wood industry. It has the uncanny ability to penetrate microscopic openings, carrying in with it whatever it's mixed with. Used straight, it's a good liniment. (I remember reading while in the military that nerve agents were mixed with DMSO to increase their "effectiveness"). This allows the ATF to penetrate the smallest crevices - even the smallest pores in the metal itself - of the inner transmission parts, keeping them lubricated with a film boundary to reduce wear. So, in our JAFE Juice mix, the ATF helps with penetrating into stuck mechanisms, and the superb lubrication base oil carried in by the DMSO helps us to slide things apart.