How long does hydraulic fluid last?

[jhp123]

My tractors get somewhere around 100-150 hrs. of use in a given year. How long should I go before changing hydraulic fluid?

 

[davesl708]

My manual recommends 300hrs on hyd./trans fluid.

 

[LD1]

Go by whatever the manual says.

I cannot remember but I think my kubota calls for oil change every 200hrs, but a fresh filter every 100hrs.

 

[KennyG]

Check the owners manual(s). I think it makes a difference whether it is a hydrostatic drive tractor or not. On older tractors where the hydraulic system was only for the lift cylinders, we never changed fluid unless it looked like it had dirt or moisture in it. If it's transmission oil, I think you are wise to change every 200 or 300 hours.

 

[bdog]

Good or bad I don't know. I have a 150k machine that has a 70hp dedicated Diesel engine for the hydraulics. This engine does nothing but turn the hydraulic pump. I think it is around 30GPM. The machine has a half dozen or so large cylinders and cycles every 10 seconds. It doesn't get used every week but when it is used it runs around ten hours a day 7 days a week. The fluid has never been changed since it was new in 2007. I would guess it has over 3000 hrs now. The reservoir is large it probably holds 75 gallons. We have busted hoses etc over the years and have probably replaced 30 gallons due to leaks from busted hoses but it has never been completely drained and refilled.

 

[LD1]

Something dedicated to hydraulic cylinders is a bit different. In a tractor, the fluid also lubricates the transmission gears and bearings as well as wet clutch discs inside. Thats why you dont want to run just plain hydraulic oil in there. Use a trans/hydraulic fluid that has additives for that reason. Those additives dont last forever

 

[Industrial Toys]

"They" always said about engine oil that it doesn't loose it's lubricating qualities, it just gets contaminated.
So is hydraulic fluid any different? If it isn't dirty and doesn't have any water in it, why change it on any sort of regular basis? I mean, do by all means get rid of the break-in period oil. That's just my thinking.

 

[big bubba]

"They" always said about engine oil that it doesn't loose it's lubricating qualities, it just gets contaminated.
So is hydraulic fluid any different? If it isn't dirty and doesn't have any water in it, why change it on any sort of regular basis? I mean, do by all means get rid of the break-in period oil. That's just my thinking.

well sort of. yes if it's not in a combustion chamber, changing intervals might be different. doing a visual on the dipstick for any fluid to me would be simplistic to say the least. refer to the model's user manual for each machine on that....if hours are in question in regard to change, the only real way to know is to get a sample analysis.... just looking at the appearance of hyd/trans fluid that may appear clear is imho blind faith... sticking to what your particular manual says is the best bet in terms of change intervals. another variable is whether the machine is parked in or out of weather...moisture can get in the hyd. case if uncovered (and moisture would be far below the dipstick).......best regards

 

[jhp123]

Hey, thanks for everyone's input on this question. I am thinking that when you look at the headache and cost of fixing/replacing anything having to do with the hydraulics, changing oil at some reasonable amount of hours is probably just a wise thing to do. Maybe it's just cheap (well not that cheap) insurance and very easy to do. Cause' as y'all know, these machines don't break until you need em' When conditions are favorable you gotta go!

 

[Mace Canute]

There's a mitt full of information here...

Machinery Lubrication Magazine

 

[mfreund]

Change the filter regularly if it is running cylinders. On my hydrostatic transmission tractor, I have to drain all the oil to clean the sump screen. I just put new in because it is cleaner. Regular recommended is 400 hrs. I went 500 with no problems.

 

[vtsnowedin]

On my gear tractor the recommendation is to change just the filter at 50 hours then go to 1200 hours before changing the oil and filter again. (and clean the screen) Hydro transmissions would probably be more often. I can tell you if you get water leaking into an open center system the oil will look milky. At ten gallons per change doing it more often then called for gets hard on the wallet.

 

[fishheadbob]

My 3930 only gets about 60 hours per year nowadays. The manual says something along the lines of 600 hours. I change both hyd filters ( optional hydraulic pump ) about every 125 hours; between the loss during filter changes, the occasional blown line, and loss from a leaky cylinder here and there I add about 2 gallons a year. The oil looks like the day I bought it and all hyd stuff works fine. Gear transmission.