2006 buick terraza with goodyear tires. experienced uneven scalloped wear at 12251 miles. dealer could find nothing wrong to cause, replaced tires for free. rotated tires every 3,000 miles faithfully. also had pressure checked with every oil change. again, uneven scalloped wear at 32000. dealer tried to claim my tires were all underinflated by 10psi causing wear. however, only 2 tires show wear, and scalloped wear pattern is not caused by underinflation. dealer service dept. refused to assist in repair or determining why tires are failing so early. service dept. manager also did not return phone calls. *tr