I use WD40 silicone spray once a month in mine. Just a little spritz in each one every month & they're smooth as glass. Simple maintenance. I do it every month along with a screwdriver to check every screw. Takes 15 minutes start to finish.
'98 Tr20 Triton completly updated & rigged, 05 Magnum c-channeltrailer
'94 Merc 200Xri completly rebuilt & noseconed/low water pickup lower unit.