Which oil for SOS

I know, I know, everyone asks this and there are a bunch of old threads. I have read a lot of them, but now it seems even more so that NH has made it even muddier for knowing which fluid to use.

I know I need NH134- however, when I search that, I get a couple of different things coming up.. from NH.

MultiGrade 134 Hydraulic Transmission Oil - SAE 10W-30 - 5 Gal./18.92 L #73344281


and I also get this to come up (it does have the different NH-401B)

Multi-G 134 Fluid (NH-410B)
A Multi-Purpose hydraulic / transmission fluid

Multi-G 134 is a single fluid for hydraulic systems, transmissions, differentials, wet brakes and PTO clutches. A high quality hydraulic oil that is truly all-purpose. Designed for use in an ambient temperature range of -5F (-20C) to 120F (50C).
Multi G-134 hydraulic fluid is a multi-purpose fluid for hydraulic systems, wet brakes, various PTO clutch systems, differentials and transmissions in farm tractors. It creates a rust- and corrosion-resistant lubrication, and is slow to oxidize. It is a medium-duty oil, with good anti-wear properties. The specifications are the same or higher than those for many other oils, and it can be used as a replacement for several, including Ford Tractor M2C134B, M2C159B2, Stieger Hydraulic Transmission SEMS 17001, White Q17001 and Allis Chalmers PF-821XL.

Am I looking at either of these? Or better off getting the top one or is something from tractor supply good enough now?

Lots of opinions here on lubricants/oils.

I have a SOS 981. I use CNH fluid in it. The Multi-G 134. I guess I have confidence that quality control for dealers might be more consistent than what ends up in TSC.

Dunno.

Dealer is pricey, no doubt. It lasts quite a while if there are no leaks to let water in.

Any *premium quality* tractor hydraulic fluid that meets Ford spec 134D should work just fine.

(quoted from post at 14:09:43 01/04/23) Lots of opinions here on lubricants/oils.

I have a SOS 981. I use CNH fluid in it. The Multi-G 134. I guess I have confidence that quality control for dealers might be more consistent than what ends up in TSC.

Dunno.

Dealer is pricey, no doubt. It lasts quite a while if there are no leaks to let water in.

Click to expand...

All SOS transmissions have a vent hole to let water in.

Any fluid that meets m2c-41a will work. The super-G is for post 86 machines with extreme high heat that the newer higher pressure systems create. Basically the m2c-41 fluid is a Type B automatic transmission fluids or what came after. In the tractor world, you can use mc2-53, m2c134, m2c134a, m2c134b, m2c134.... up to the (synthetic blend) super g /m2c134g ambra super g fluids. While later 24 speed tractors MUST use the newer oils, you can or cannot and just an oil that meets the original specs as that oil performed well. As hydraulic pump pressures increase with higher flow rates, the temperatures started increasing dramatically after 1976. But the original minimum spec for the sos is very low, as was the original type b and later type f automatic transmission fluids. Tractor supply has the 134c spec fluid for around 49$/5 gal on sale two times a year that is around 4 specs newer/higher. Or buy the synthetic blend ambra (134)multi-g $80-$130 for 5 gal from a new holland dealer.

I use CNH 134D but any modern hydraulic oil meeting the CNH 134D spec will be fine.

DO NOT uwe the new CNH hydraulic oil (can't remember what this is called at this time).

Respectively, all of my SOS's have a vent but there is a loose fitting cap over
them to keep any water out. Granted you may still get some condensation from the
air but no rain water.

(quoted from post at 21:47:55 01/05/23) Respectively, all of my SOS's have a vent but there is a loose fitting cap over
them to keep any water out. Granted you may still get some condensation from the
air but no rain water.

Click to expand...

I took the cover off from mine for the second time yesterday. I have had it for over twenty years, and for all that time annual oil checks with scheduled changes have kept the oil clean. Yesterday I noticed old rust under the cover. It has to be from condensation before I got it, proving that even without leaks, water is going to get in and must be watched for.