So lately my Fox 36 Van 160mm has been making a lot of clunking noise when it is moving in the travel. It never used to do this and sounds like the spring might be loose? I have the preload knob screw in a couple of turns and everything on the fork feels solid, all the bolts, caps; everything is tight and there is no play in it. It sounds (and feels) almost exactly like how my Fox 40 did, with its long spring slapping away inside of the fork. Should I be concerned or is this normal? The fork is a 2008/2009, I think.