I had trouble getting a hydraulic hose connection made up, FEL to rig. Finally got a different hose end in than got the proper color hose connected. I slid the collar back, but the balls around the circle wouldn’t go in to allow the male to seat properly in. I had cleaned up all the connections with wd-40 in the past but feel fluid film would work better to prevent any grit or such that might have gave me the trouble. Big question is, will it rot out the coupler O-ring ? I thought I had read on the fluid film label that it corrodes rubber and such.