Thanks for your replies.
The scraping sound (when the steering wheel is at full turn position) magically became quiet in these couple of days. Dealer found no problem.
The dealer said the brake pads and rotors should be replaced and estimates the total cost to be about $550.
I postponed the job because I already spent apprx. $ 2k 1~2 weeks ago at the dealer, and am now out of money.
The dealer said that the transmission pan should be replaced.
Transmission pan "gasket" was replaced just 1~2 weeks ago at the dealer due to leak. But they said it leaked again this Thursday.
This time, they did not charge labour cost for transmission work.