<font face="Verdana, Arial" size="2">Originally posted by Joon525:
Yeah I see what you are saying........I just thought of it this way....if you heard a metal on metal "banging" noise, it can only mean that there's space between the 2 pieces. Hence if you made the collar longer it would eliminate this noise by taking up the space that was available for the 2 parts to travel in. See what I mean?
Don't get me wrong though......your explanation DOES indeed make sense to me...I'm wondering what what happen if you did the collar swap AND the washer trick???
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I thought something similar. But now I think the metal/metal contact occurs during a wiggling or side-to-side motion of the shock shaft, not a vertical motion. This is why the bushing comes into play as it is there to absorb all such lateral motion yet also ensure vibration of the shock shaft isn't transmitted directly to the body (bushings are rarely used anywhere in suspensions except for comfort/noise concerns; ideally everything would be welded to everything else
).
Notice there are two bushings and they are separated by a plate; there is really no up-and-down motion (along the axis of the collar) that can occur as the upper plate always clamps down quite solidly on the collar, so there can't be any movement between the top of the shock and that plate unless something is very loose.
To your question about the new collars and the washers both being used, I think that would just allow the top bushing to be compressed even further. This might be too much deflection of the bushing however and that might cause the bushing to deform somewhat and actually do more harm than good (similar to Matt's comments about not adding too many washers in his fix). I have a feeling any further improvement would be in working on the bottom bushing area, or just using tougher bushings.
NVR2FST: Your experiences make sense to me, as it is ultimately still the bushing that does the work of keeping all the metal parts separate. The stock collars are just a bit too long to allow the bushing to be sufficiently compressed. New bushings would be best, though I would also want to replace the lower bushing which isn't nearly as easy to get to as the upper. I'd also like to use a much firmer bushing, even if it did transmit more vibration to the body. Unfortunately I don't know of anyone who sells these bushings in a different material....
Kraut
