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WE HAVE A PROBLEM WITH TIRE CUPPING ON OUR 2004 VIBE, NO ONE CAN FIND ANYTHING WRONG WITH THE FRONT END MECHANICS, DOES ANYONE KNOW WHY THIS WOULD HAPPEN. FRONT END DOES NOT NEED ALIGNED, STRUTS ARE IN GOOD SHAPE TIRES ONLY HAVE 28,000 MILES. ROTATED EVERY 7,000 MILES AND THE LAST TWO ROTATIONS HAD A VIBRATION IN STEERING WHEEL AND A LOT OF WHEEL NOISE. THEY ARE KELLY NAVIGATORS GOLD TIRES WHICH ARE NOT BOTTOM LINE.  

First, if I have a problem with the term "cupping".  It's supposed to be used when the problem is balance or shock related.  It's an old term that referred to what bias tires would looked like if the tire was out of balance or had a bad shock.  The tire would look like someone had taken a cup and scooped some of the tread off.  This occurred in a single spot.

Modern radial tires do not behave the same way and the appearance is totally different when the problem is balance or shocks.

But it is more likely that tire wear problem are caused by mis-alignment, so I think a better term is irregular wear.

So the second point would be that the alignment is NOT OK - and in this case the problem is the specification.  Vibe's and Matrix's have too much camber specified - anything over a degree seems to cause problems.

So your first step is to find an alignment tech who is willing to dial out the camber to less than a degree.  This may require some shim kits or a camber plate - and it may result in some other issues to get it set right.  Oh, and the toe should be set really close to nominal.  "In Spec" is NOT good enough!

And lastly.  Please turn off the caps.  Not only is it difficult to read, but it comes across as shouting.  If you want people to read your posts, they have to be user friendly and all caps isn't!