Once they start acting up, it takes a bit of work to get them moving well again. I had to pressure wash, spray liberally all movement points with penetrating spray, use them for a few days, pressure wash again, spray with penetrating spray, etc. After a bit they started working reliably and then I washed them good again and sprayed them with a silicon lube. They have been working good for a bit now but winter is hitting now, so I suspect they will start getting gunked up a bit. I really think that these need to be cleaned well regularly and lubed regularly. Fluid film is not a popular thing in my area but I have wondered if that would be a good thing to do on these in the winter.
Interestingly enough, my issues started mid-late summer after just dusty road driving that didn't include much wet and muddy driving.
WD-40 isn't a good lubricant, its not super good at much of anything to be honest. Slightly better than nothing but not by much.