Clunking noise in front suspension

Discussion in 'General Motoring' started by George Rhude, Jan 21, 2007.

  1. George Rhude

    Bill Putney Guest

    What happens is that, as the two front wheels get tossed up and down
    relative to each other, each side of the sway bar gets pressed hard
    either upward or downward against its bushing - creating a temporary gap
    between the sway bar and the bushing on the other side of the bushing
    hole. Then the direction of the force on the sway bar rapidly changes
    direction and the gap closes and the sway bar slams against that side of
    the hole in the bushing - the clunk noise is created and reverberates
    thru the frame.

    When the sway bar is not under stress, there are no gaps - even after it
    is worn out, the diameter of the bushing hole is still (unless *really*
    *badly* worn out) slightly smaller than the diameter of the sway bar,
    and you can't create enough force with your hand to create any gaps. So
    the bushing looks fine to you. When it was new, the bushing hole
    diameter was smaller, creating a lot more pre-load (pressure) against
    the sway bar diameter, so the gaps didn't occur under load.

    It's the ten-times-greater forces than you can create with your hand
    that creates the gaps and slams the sway bar against the sides of the
    bushing hole that makes the clunking noise with a bushing that, with no
    load, is in contact all around the sway bar (i.e., a bushing that looks
    fine).

    Bill Putney
    (To reply by e-mail, replace the last letter of the alphabet in my
    address with the letter 'x')
     
    Bill Putney, Jan 28, 2007
    #21
Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.