Using Wrong Hydraulic Fluid

[Silver_Knight]

So I just realized that we have been supplementing/adding the wrong hydraulic fluid in our JD 323E skid loader. We changed the hydraulic fluid a few months ago due to milky looking fluid. The unit was flushed and the correct fluid (HYDRAU) was installed.

We have been adding HY-GARD instead of HYDRAU. Can't really find anything at the dealer or online regarding this. Any suggestions on problems? Should I just empty and flush again? JD Tech support states that the correct fluid HYDRAU is about 40% thicker but didn't know any other information.

 

[BeezFun]

This JD publication gives a lot of info on both products. The Hydrau description says: "These products are not for use in mechanical transmissions, axles, or multi-function systems featuring gears, clutches, or wet brakes, requiring a Transmission Hydraulic Fluid (THF, like Hy-Gard). So it would seem to follow that Hy-Gard probably shouldn't be used in place of Hydrau. If it were me I'd do a flush and switch back to the Hydrau. I think I'd cycle all the hydraulics in the right order to try to get as much out of hoses and cylinders as possible.

 

[dodge man]

I think Hy Gard is a low viscosity fluid, I’m guessing the other stuff isn’t. I doubt you hurt anything but I would swap it out. I’m not sure I’d flush it though.

 

[DMW]

You're using a more expensive fluid to top up the machine. The viscosity (thickness) of the Hygard is between Hydrau (ISO 68) and the synthetic version Hydrau XR (ISO 46). Don't use Hydrau in place of Hygard, but Hygard as a supplement to Hydrau should not cause any issues.

Just want to add, how much has been supplemented? Is it any different than moving attachments between machines? Adding Hydrau in the future would be preferable.