Two-post lift hydraulic fluid foaming issue

[JamesonRacing]

Have an off-brand two post lift, probably ten years old.

Having an issue when I lower a car - the reservoir fills with foamed fluid.  I can wait a little while and the foam settles and I can lower the car, but more foam shows up.

No obvious source for aeration into the fluid, and it seems to lift fine, although probably slower that when it was new.

Thoughts on what's happening?  New power unit or gasketing?

[My427stang]

I have heard either switching to a synthetic hydraulic oil or adding a anti-foaming additive will fix it. It hasn’t happened to me per se but I saw it happen on base and they used an additive

[RustyCrankshaft]

Change the oil and use ATF, or AW32 or 46 which usually has anti-foam additives in it. Usually fixes it and for a small amount is usually less than buying the anti-foam additive alone.