I just asked the same question over in the Lub/Fluids forum. The manual for my 3510 states to use TF500 fluid. I was sold 5-gallon buckets of 76 Tractor/Hydraulic fluid. The compatability list was very long, but it didn't say TF500 anywhere. SoundGuy helped me out with the following, which I hope it is okay to plagerize here, since it probably answers your question:
Is your 76 hydraulic/tractor fluid a UTF fluid.. look on it for compatibilities.. if it is equivalent to hytran, hygaurd.. NH M2c134d or JD 303 fluid.. it is a UTF fluid.
That said.. most tractors that use common sumps for hyds, tranny, and diffy use UTF ( but not all aparently! )
Different manufacturers have different names. For instance.. at work, we use FINA oil products. Thier version of UTF is TF56 standing for torque fluid 56... perhaps yours is similar.
Check it out before using it..
Soundguy
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