Premature rear tire cupping and size differential. on 2003 Ford Focus

Rear tires cup prematurely on the inside of the tires making it necessary to buy a new set of tires every year. I have the ZTS model with P205/50R16 omni-directional tires (low profile). My nephew has the SE model that has P195/60R15 bi-directional tires that are a higher profile. Why the difference? Car has been aligned yearly. Tires rotated regularly. Mechanic says "no problem". Any help?

by in Osage, IA on August 09, 2010
Get Your Car Fixed at a RepairPal Certified Shop.
We certify shops based on expertise, quality work, and verified customer reviews
1 answer 2 comments
ANSWER by , December 07, 2010
I own a 2004 Focus, having same problem. Tried alignment 3 times, glad I bought the "lifetime alignment" though it didn't help. Someone suggested replacing struts. Did this. no change. I rotate regularly so I couldn't tell if it was a front tire problem or a rear tire issue. Sounds like I am not alone. Ready to sell it; tired of buying new tires every year, too. Sigh.
COMMENT by , December 09, 2010
Car has been killed by a deer, so no more problem with it, but I replaced it with a 2001 model which does not seem to have the same problem so far. I also have a 2006 model which also does not have the same problem. I think a design flaw in the 2002 to 2004 models?
COMMENT by , July 19, 2011
We have a 2001 wagon that has the same problem. Ready to give up on it.