My 91 scarab has the original IMCO external hydraulic steering setup and I am not sure what fluid I should be using in it. I saw an old thread where ATF was recommended, and what is in the pump now looks to be ATF. I have not bought ATF in a few years and was surprised to find about 5 different kinds of automatic transmission fluid. Is Type F what I want to use if in fact ATF is what I should be using?

I use plain old PS fluid.

I called imco the other day about the fluid since I had pulled my motors out over the winter and needed to refill the system. I still had a little atf in the system and they told me to get out as much atf as possible and refill with a quality ps fluid. The atf eats up the seals in the pump over time.

Imco told me standard power steering fluid as well.

have been told only to use the high performance non-foaming P/S fluid from GM