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GT18: hydro fluid change, type?

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#1 djordje33 OFFLINE  

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Posted June 13, 2018 - 09:57 AM

Going to pull the fluid from my system for piece of mind and typical maintenance. notice that the manual is calling for 5w30. i use hygard low vis JD fluid in my deere tractors which have the same hydro, but i'll stick with the manual on the ariens. 


is it okay to jump to a full synthetic 5w30 motor oil, or is there some taboo and conventional is preferred? noticed that there are also some 5w30 oils targeting hydro transmissions. any difference? 



#2 dodge trucker OFFLINE  

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Posted June 13, 2018 - 10:43 AM

Since you won't get it all out unless you completely disassemble the unit, or change the fluid and filter several times back to back with just enough use in between to stir everything up and mix it all together inside before draining, maybe one of these synthetic blends might be a good compromise?
I wouldn't use synthetic oil in just everything but I do see advantages in some applications. This being a hydraulic application where fluid is being pumped around, not sure about but in a splash lube application I have seen it make a difference. I had a 4x4 plow truck some years back and the front axle disconnect mechanism wouldn't always engage properly when it was cold outside, I switched to a synthetic axle lube and never had another problem. I have heard that you shouldn't switch from conventional to synthetic on an older unit because of possibly new leakage developing because the existing seals are conditioned to that style of lube. On my truck I had recently had the front diff apart and put new seals into it throughout and had run the conventional stuff for a short time before I switched

#3 Kurtee OFFLINE  


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Posted June 13, 2018 - 02:31 PM

I would use the Hy-Gard. It is meant to be used in a hydro. Modern motor oil is not good for any hydro as formulations have changed and there is none of the additives the transmission needs. Motor oil was used as hydro fluid years ago by several manufacturers in skid loaders including Case and Bobcat and they no longer use it. I have an Exmark mower that recommended Mobil 1 when I bought the machine about 10 years ago and they no longer tell you to use  that due to a change in the formulation. If the fluid meets John Deere, Bobcat, Case-IH, Cat specs for hydro fluid use it or take your chances with something else. Pay me now or pay me later is one way to say it.