tires cupping

[Wayne Cox]

At 11:38 AM 12/20/2002 -0600, you wrote:
>I got my alignment done on 12/7. Now the right side is cupping on the
>extreme outer edge. I just called the people who did the alignment and
>they told me:  "that is due to balance and lack of rotation, not alignment"

Cupping is supposedly due to vibration issues, like wheel balance (would
probably have to be WAY out) or bad struts (seen those cars where the
suspension "dribbles" the tire down the road?)  I guess really loose
bushings, ball joints, or something bad in the steering (rack or tie rod)
that let the tire "wiggle" as it rolls could cause it, too.

Rotating the tires is not going to stop excessive wear caused by some other
problem - it merely spreads it out over all the tires so its less noticeable.

Alignment problems usually cause wear that is even around the
circumference, but to one side of the tread width.  eg:  a toe problem
wearing the inside shoulder quickly but evenly.

    -Wayne    '91 NX2k - '93 NK2k - '92 SE-R parts car