Does SUDT ever "go bad"?

[sandalwood]

I'm about do to HST/hydro fluid & filter service. I purchased Kubota filters and SUDT, only to find I still had about 1.5 gal of SUDT left over from last change 2-3 years ago. SUDT stored inside in basement garage. With the price of this stuff, I hate to discard it, but don't want to risk damage to tractor if issues like moisture content or stability of oil components over time could be a problem.

Anyone know if there is an "expiry date" for SUDT?

 

[number two]

Use it up first,then continue filling with your new stuff,as long as condensation isn't present.Water,if you had it,would be at the bottom of the container.I agree,at the price of it,don't throw it away.I use it also and am well aware of the price.

 

[MessickFarmEqu]

From what I've heard additive packages do breakdown over time. I doubt your going to hurt anything though.

 

[sandalwood]

Thanks for the replies. I don't expect any major problems since the "old stuff" will only make up a small portion of the total volume.

 

[john_bud]

Does SUDT "go bad"?

Well, I saw a couple quarts on the corner under the street light smoking cigarettes and passing a brown bag back and forth. Does that count?

 

[dirtworksequip]

I've used CAT motor oil and hydraulic oil I've had for longer than I can remember. 10 plus years. No engine problems or burnt up hyd. pumps yet. How would it break down in a sealed container? What physical forces would be acting on it?

I think oil is like diesel fuel. It has a lot longer storage life than we think.
Sincerely, Dirt

 

[4shorts]

Does SUDT "go bad"?

Well, I saw a couple quarts on the corner under the street light smoking cigarettes and passing a brown bag back and forth. Does that count?

 

[DieselPower]

Yes all oils will go bad over time. I usually recommend using oil before the 5-6 year mark. A unopened container will have the longest shelf life. Once opened deterioration will occur a little faster due to oxidation caused by the introduction of oxygen into the container. Additives will also break down over time and will also drop out of solution. Your 2-3 year oil should be fine.