Power steering fluid for 1971 Ford 4500 backhoe

[Cornell]

What type of fluid should I use in the power steering reservoir? Been using automotive power steering fluid and it bubbles out of the vent at the top of the reservoir until it's empty.

 

[Smokeydog]

The Ford dealer told me the same tractor hydraulic/transmission fluid could be used everywhere.
Had a small leak on the power steering cylinder. Had to periodically add fluid. Used a 2liter coke bottle that I kept in the tool box. Didn’t take much oil and cheaper to feed than fix. Could see lots of bubbles when filling.
The ps pump has a circular filter. Got a filter and gaskets but never changed.
The repair manuals was a set of 9 books. Well written and easy to understand.
Had the 4500 for over 20 years on the farm. One of the best running diesels I ever had. Sold it for what I paid for it.

 

[RickB]

Change your filter and use your preferred universal tractor hydraulic oil.