WHILE TEST DRIVING A NEW CADILAC SRX EQUIPPED WITH AUTOMATIC ALL WHEEL DRIVE, V-8 ENGINE AND 20" TIRES (OVERSIDED THE REG 18" STANDARD TIRES AND WHEELS) VEHICLE STEERING FROZE MAKING LEFT HAND TURN GOING APPROX 10-12 MPH....RIGHT FRONT TIRE AND WHEEL . FAILED...CAUSING SKID INTO CURB....PRELIMINARY INSPECTION SHOWED FAILURE OF ALL WHEEL DRIVE OR RIGHT WHEEL LUGS/TIRE FAILURE CAUSING LOSS OF TIRE/WHEEL.*AK