[abdulloh]

How should we make our own transmission fluid and power steering fluid by possible sources from chemical stores, natural environment, etc ?

[pcm81]

How should we make our own transmission fluid and power steering fluid by possible sources from chemical stores, natural environment, etc ?

Well, to do it trul;ly from scratch, you first need to locate an oil deposit, buy the land and build an oil rig.
Then you need to buy more land and build a refinery...
Then you need to hire a bunch of chemists and engineers that can design a good transmission fluid for your specific application.

Skip to step 3 if you can locate needed chemicals in stores.

[Enthalpy]

You mean, a hydraulic fluid?

There are hundreds of them, depending on the desired properties. They are difficult to develop, because some drawbacks must be addressed precisely. Like: wetting ability, defoaming, corrosion protection, viscosity index, behaviour under extreme load, and so on.

So just trying quickly won't work. This is a hard process.

Vegetable oils are a decent start. At least, they lubricate and don't corrode, and they are biodegradable. They serve (with additives!) in forestry machines.