The spec of the oil is determined by the engineers that designed the lift. ISO 32 is roughly equivalent to 10W engine oil whereas 68 is about 30W. The thicker oil will slow down the reaction time of the hydraulics & will put more of a strain on the hyd, pump.

I'll use thicker oil if the hyd pump is worn as a stop-gap until a replacement pump can be sourced

I just returned from Northern tools and they have a iso 32 light and an iso 68 heavy obviously a difference in weight,

question, What determines which weight: type of equipment, type of work (lifting heavy v light) temperature? The iso 68 is on sale $8.00 off 5 gal.

Yes. Just make sure it's a good known brand

I took back the oil from ED. I looked at autozone and they have R&O ISO 32 Light Hyd Oil for 45.99 for 5 gallons. Will that work?

I'll have to look at the specs of the oil tonight. I just went to equipment depot and asked for hydraulic fluid and that's what they gave me $63 and change for 2.5 gallon jug.

I don't think I have too much in there. I have a good leak I was able to trace down this weekend. Its where the power steering lines come down from the pump and head across that cross member I guess going to the sump tank. There is a line with a tee and its leaking pretty good. It looks like the pressure line, I assume the line with the worm clamps is the return line. I don't know if its loose or the line itself is leaking. Tight down in there with the steering cylinder

I could not figure it out till I got under it and scraped off 30 years of dirt, gunk and crud (filled a 5 gallon bucket) Now I can see whats going on.

119? Standard R & O hyd oil is all you need (about $10/gal)
- what spec oil are you pricing?

No dis-respect to mr fixit but I would change the oil. I just learned a valuable lesson when I had to eat the price of a hoist cyl rebuild- there may be the tiniest of particles in the oil -which- in the long run can destroy cyl packings. I now include a flush & oil change of the hyd system on every hoist cylinder rebuild I do if the customer wants a warranty.

I don't think so. I would lift the forks up all the way to reduce the amount of oil in the tank. Then take the flanged piece off the top of the tank where the big suction hose connects to get at the filter. If the oil doesn't look horrible then I wouldn't worry about changing it. $119 ?? Something ain't right there.