My front end loader moves slow. Do I have to use the jd hydoguard fluid? I heard of cleaning screen and changing filter. Has anyone run into this? Can I use a little lighter weight hydro fluid? Somthimg to look for?
Loader speed is governed by pump flow, which is governed in turn by engine rpm.
Restricted filters or screen can limit the flow. A fluid temperature that is low will cause the system to be sluggish for a few minutes after it goes to work, and a fluid temperature which is too high will cause the fluid to thin out to the point that it can't transmit power.
Hydraulic pumps have a positive displacement and at normal operating conditions will generally move a specific volume of fluid with each revolution, whether the fluid is high or low in viscosity.
JD sells oil and while the equipment is under warranty, it is best to use what they recommend. After warranty, I would look for an oil that is compatible, but at a more easy to swallow price. There are many hydraulic fluids that will handle the general conditions that your loader will be working with.
JD recommends Hygard fluid for the hydro in the JD 400 GT. MF recommends ATF Type A (Dexron) for the hydro in the MF1655 GT. Both hydros are identical Sundstrand Series 15 inline models and Sundstrand states that "most good quality hydraulic fluids are acceptable". Other tractor manufacturers spec motor oil and ATF Type F for the same hydro. Who do you believe?
Back to your question of using lighter weight oil. If you are in a cold climate, you can use Lo-Viscosity HyGard. In the 650, there is no wet clutch or brakes, so fluid choice isn't as critical, but I would still be sure to get something that meets JD specs to be sure of getting high quality oil.