Senior Moment Regarding Oil

Hi all - Now that frost is just around the corner, I'm getting serious about landscape rearrangement. I want to add to the HT4 hydraulic tank, possibly change out the oil altogether, depending. Manual says 10W mineral oil, what is a modern equivalent? or will a modern equivalent do harm? my working life has been with rubber tired green and the thought of not adding Hyguard to a hydraulic system is giving me a brain cramp I've read everything on here about oil and I'm still feeling stupid thanks for the help

AW 32 hydraulic oil is equivalent to 10 weight. Most universal tractor fluids are higher viscosity AW46 or 20 weight. I doubt you will have any trouble with using any of the quality tractor fluids including the cheap yellow bucket 303 fluids.

I think the biggest issue with the "303" fluids is the effect on modern wet brake/clutch linings. I went through the brakes on 4 JD tractors this summer and do not plan on using the cheap stuff ever again. I think the old riveted linings could stand a lot more than the new asbestos free bonded linings. I found lots of bonded linings that could be peeled off with a thumbnail!

I use the Walmart Tractor hydraulic fluid in everything. Even Allison transmissions. Had an analysis done on it years back and it was the same as Shell tractor hydraulic fluid. It is compatible with every fluid made for hydraulics, transmissions and wet brakes.