I figure you probably don't want to get under the car much, but another thing to check is the starter. Yes, starter. Take the plastic inspection cover off (2 bolts) and try to move the starter gear in and out with your finger. It should move but spring back. If the return spring gets weak or breaks, the starter gear can kiss the flexplate because it can slide over during cornering due to inertia. Makes helluva embarrassing racket if its completely gone bad. Sound is difficult to pinpoint, is intermittent, and it echoes off curbs. Easy to check and you'll know if thats it right away. Replace starter is the fix.
