ISO32 or ISO46? Which one?

[Norman]

I live in Newnan Georgia, about 30 miles south of Atlanta. I'm getting a new Woodland Mills WC68 chipper that specs the ISO32 (or ISO46 in "warmer climates"). Does it really matter to me which one I use? Winter temps here rarely get below 30F. Would one perform better as an "all season" hydraulic fluid? I'd like to buy once and be done. Everything I've read indicates that either one would be okay to use but I wanted to get some real world opinions too.

Thanks again for responses, I'm pretty new to this tractor thing so have a steep learning curve.

 

[TheOldHokie]

I live in Newnan Georgia, about 30 miles south of Atlanta. I'm getting a new Woodland Mills WC68 chipper that specs the ISO32 (or ISO46 in "warmer climates"). Does it really matter to me which one I use? Winter temps here rarely get below 30F. Would one perform better as an "all season" hydraulic fluid? I'd like to buy once and be done. Everything I've read indicates that either one would be okay to use but I wanted to get some real world opinions too.

Thanks again for responses, I'm pretty new to this tractor thing so have a steep learning curve.

Let me give you a reference point. Super UDT2 is a ISO 46 oil and well suited to all season use in hydraulic systems. However it has a much higher viscosity index than a conventional hydraulic oil so its viscosity is more stable across temperature changes.

In your application the choice of ISO 32 vs ISO 46 comes down to two factors:

1. You want it to be pumpable in the coldest temps you will see. Above 32F both are going to be perfectly fine.
2. You want it to retain viscosity when running heavily loaded for extended periods and at high temperatures. Again both are going to perform fine. If you are going full bore for extended periods in 100F plus weather the ISO 46 might have a small advantage.

I know - not particularly helpful
So based on your comments the OEM seems to prefer ISO 32 for general use and that would be the deciding factor for me.

Dan

 

[Norman]

Let me give you a reference point. Super UDT2 is a ISO 46 oil and well suited to all season use in hydraulic systems.

In your application the choice of ISO 32 vs ISO 46 comes down to two factors:

1. You want it to be pumpable in the coldest temps you will see. Above 32F both are going to be perfectly fine.
2. You want it to retain viscosity when running heavily loaded for extended periods and at high temperatures. Again both are going to perform fine. If youbare going full bore for extended periods in 100F plus weather the ISO 46 might have a small advantage.

I know - not partichlarly helpful
So based on your comments the OEM seems to prefer ISO 32 for general use and that would be the deciding factor for me.

Dan

That's helpful. I wasn't aware that the UDT2 is ISO46. I kind of thought either would be good, but given the investment and the fact that I like to take care of my equipment I wanted to gather some more information before making the decision. I want to get the right stuff to keep this thing running optimally for years. I doubt I'd run it in very hot weather unless its an emergency of sorts. Otherwise it will run 30F-80F ambient conditions most likely. I do have 5 acres, of which a substantial portion had a tornado go through earlier in 2021 so I'll be running it often while clearing brush.

 

[PoTreeBoy]

I live in Newnan Georgia, about 30 miles south of Atlanta. I'm getting a new Woodland Mills WC68 chipper that specs the ISO32 (or ISO46 in "warmer climates"). Does it really matter to me which one I use? Winter temps here rarely get below 30F. Would one perform better as an "all season" hydraulic fluid? I'd like to buy once and be done. Everything I've read indicates that either one would be okay to use but I wanted to get some real world opinions too.

Thanks again for responses, I'm pretty new to this tractor thing so have a steep learning curve.

I'd consider 'south of Atlanta' a warmer climate, so ISO46. But if all I had or could get was ISO32, I wouldn't lose any sleep over using that.
If I was feeling rich and wanted to standardize, I'd use UDT !

 

[TheOldHokie]

That's helpful. I wasn't aware that the UDT2 is ISO46. I kind of thought either would be good, but given the investment and the fact that I like to take care of my equipment I wanted to gather some more information before making the decision. I want to get the right stuff to keep this thing running optimally for years. I doubt I'd run it in very hot weather unless its an emergency of sorts. Otherwise it will run 30F-80F ambient conditions most likely. I do have 5 acres, of which a substantial portion had a tornado go through earlier in 2021 so I'll be running it often while clearing brush.

The ISO viscosity grading system is a lot easier to understand than the convoluted SAE system. The ISO grade number is simply the viscosity (+/- 10%) of the oil measured in centistokes at 40C. So an ISO 46 oil has a viscosity of 42-50 centistokes at 40C.

I lied to you when I said SUDT2 is an ISO 46 oil. I should have checked my memory before posting. The original SUDT had a viscosity of 45 cSt @40C so it was an ISO 46 oil. The reformulated SUDT2 has a viscosity of 37cSt @ 40C so it is actually just barely out of the ISO 32 range. (29-35 cSt). Thats why Kubota recommends SUDT2 for cold weather use.

Dan

 

[nbryan]

I just use the

I live in Newnan Georgia, about 30 miles south of Atlanta. I'm getting a new Woodland Mills WC68 chipper that specs the ISO32 (or ISO46 in "warmer climates"). Does it really matter to me which one I use? Winter temps here rarely get below 30F. Would one perform better as an "all season" hydraulic fluid? I'd like to buy once and be done. Everything I've read indicates that either one would be okay to use but I wanted to get some real world opinions too.

Thanks again for responses, I'm pretty new to this tractor thing so have a steep learning curve.

Just go with the ISO 32. This is a simple belt driven hydraulic pump running the chute drum motor, and it takes 5 gallons to fill. Not like it's going to be working very hard even in your warmer than my Manitoba climate. I've had the same ISO32 in my WC68 tank for the last 3 years of use, all's good.

 

[NCL4701]

When I bought mine I was all wound up about the 32 v 46 issue so I called Woodland Mills tech support and asked them since they made (or at least designed) it.

They said it’s not really that big a deal either way unless you’re routinely running it in a really cold climate such as Canada, Alaska, and maybe some of the far north US. For NC they recommended 46. I asked about synthetic v dino and recommended brands. Again, they said it’s a pretty simple system that’s not all that sensitive so not very important, just whatever was cost effective. I run 46 based on their recommendation but it sounded to me like running 32 should work as well.

If you’re still concerned about it, I’d suggest call Woodland Mills tech support and ask them. Being you’re in Georgia I suspect they’ll recommend 46, same as they recommended to me.

For some systems, such as HST transmission in a tractor, specific fluids may be really important. For this thing, not so much.