Word of caution:
I'm intensely familiar with this sound and having gravel in the brakes.
In my case it occurred repeatedly for approximately two months. Never while the vehicle was moving, always after it had been parked. Usually in the same location but gravel also found it's way into brakes while vehicle was parked in a number of other locations.
Gravel would come out obviously crushed when one flexed the shroud. All would be good until the next occurence. That occuring alongside two vehicle entries that seemingly bypassed entry security was too much for me and in paranoid investigator mode, looked into it, suspecting vehicular inteference.
Discussion with many service agents lead to perception that "once or twice in a vehicles lifetime" was a norm for something like this happenning "randomly". So the overwhelming statistical significance of repeated instances strongly suggest inteference - i.e. someone willfully placing gravel in the brake assembly.
Took to service and requested brakes be inspected in detail, particularly front, gravel shrouds, Gravel was found in the disc. The going theory is that gravel was placed so as to obstruct the calipers, was then crushed at which point to get's caught in the rotor, eventually it makes it's way out, at which point in fouls between the gravel shroud and disc. On one occaision it was so severe that when jacked up after stopping almost immediately, the gravel jammed in there was a very significant impediment to the rotation of the wheel and tyre.
There's more to the story, but suffice to say that after someone saw me seeing them loitering near the vehicle, all instances of gravel intrusion ceased.
I expect it would be near to impossible to place gravel as necessary to do this deliberately with the stock wheels. I have a much more open wheel face that would make it easier.
So I'd be (a) interested in hearing from anyone who has experienced anything similar in order to gauge norms, and (b) asking if you have aftermarket wheels with an open face?
I don't know exactly where the gravel was placed, so someone very familiar with the OEM brake assembly might be able to detail that?
Last edited by Nexus; 01-08-2010 at 01:03 PM.
Reason: Caveat
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