by Robert Sanborn on Thu, Aug 10, 2006, who was a member of the STLE Society of Tribologists and Lubrication Engineers for 15 years.
**Yes, it has been shown that H-Zol will smooth the shifting with power shifts in hydrostatic transmissions. But, because they work on a limited friction basis do not add more than one (1) ounce H-Zol per quart of hydraulic fluid as slippage can occur if you do not follow the recommended dosage. In all other hydraulic applications you can add up to one and one half ounces per quart of hydraulic fluid. **