When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The reservoir in my '95 302 powered E150 is a bit low. I might as well remove as much of the old fluid and replace with new. Per the owner's manual:
Use only power steering fluid that meets Ford's spec ESW-M2C33-F, such as Ford Premium Power Steering Fluid, E6AZ-19582-AA or an equivalent Type F ATF with a Ford registration number (an 8-digit number beginning with 2P printed on the fluid container)
I have a nearly full bottle of Mobil 1 synthetic ATF that is Dexron-III/Mercon rated and two quarts of Valvoline MaxLife High Mileage that has the same specs. Could I use either one of these or is Type F crucial? Also, is ATF hydroscopic like brake fluid? The Mobil 1 fluid is new but the bottle was opened a long time ago as I used it as top-off in another vehicle.
Type F and Dex/Merc are not compatible. While a lot of people do use transmission fluid in their power steering, I'd be very leery of using a type that isn't compatible with what Ford recommends.
Power steering pumps aren't that sensitive, all they are is a hydraulic pump, you could use just about any hydraulic fluid in them and they would work fine, as long as its the right viscosity. They don't have clutches in them like a transmission does that requires a certain type of fluid.
Like many I use whatever ATF I have on hand, try to use something fresh or unopened though. I never leave caps off any fluid bottles but if the foil seal is broken over time moisture creeps in, AFT loving moisture and vice versus.
Its good to be concerned and ask if uncertain about something but in this case its not a super critical requirement.