the swing cylinder on my metavic forwarder trailer is buried down in the enclosed headboard, with only removable covers for access. finally took a look in there and low and behold the end cap was working its way loose, having destroyed the o-ring and rubber backer. parts are ordered and it only oozes a bit, though I won't be working it very hard till it is fixed. I checked my other cylinders and the main lifting one is also loosening. I have asked around and apparently this is a common occurance on hydraulic devices. One fix mentioned is to drill a small hole and insert a screw to stop the motion. anyone have any other fixes?