Help! A worrisome 'growling' sound has grown louder & louder over the last 60 days. I purchased 2005 Focus SES 5-Speed NEW. Love this car. At present it has 243,000 miles. Dec 2012 I spun out (full 360 degrees) on slush climbing a "S" hill and right-rear touched guardrail. Four inches of the "frame" bent. Four-wheel alignment done. Jul 2013 I did a full rear brakes job (new drums/hardware/ bearings). Curiously the RR tire has unusual wear right down the middle. So I got two new tires but 'growling' sound remains. Thoughts please?