I was just looking on another Polaris forum, trying to get an answer to the same question. In addition to the Universal fluid available at Tractor Supply, they also carry Mystik JT-5. A couple people on that forum said they did the research, and, the Mystic JT-5 fills the bill. Nice to know. Here is a quote from their website:
"MystikŪ JT-5 Trans Hydraulic Fluid delivers excellent performance in modern agricultural equipment and exceeds requirements of John Deere J20C.
•Offers outstanding gear wear protection, brake chatter control and oxidation resistance
•Particularly well suited for hard working applications where an added level of protection is desired
•Excellent filterability characteristics along with rust corrosion inhibitors, water tolerance, and wide temperature range performance
MystikŪ JT-5 Trans Hydraulic Fluid, 2 gal. - Tractor Supply Co.
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