ToddM 0 Posted October 15, 2000 Doing some pre-winter maintenance on my 7012H today and removed the hydrostatic filter. Expected it to be filled with ATF since that is what is specified, but it was filled with hydraulic oil. I was taught not to mix oils. Perhaps in the "old days" manufactures used different additives that were not compatible,I don't know about today. But, I'm going to drain and flush the entire system. Anyway, the reason I'm posting this message is to give a tip to those who do not have a mechanical background. Buy a small quantity of motor oil, ATF, gear oil, hydraulic oil, brake fluid, etc. and examine them. Each has a distinct odor and viscosity. This knowledge is helpful when working on your tractor. Share this post Link to post Share on other sites