At about the same mileage my 06 started acting up also. The torque converter wouldn't lock up. The local dealer coundn't find anything wrong even with a P1740 code. I said goodbye to warranty and the cruddy dealer mechanic and had a Goering converter and valve body put in so I won't be worrying about the under enginered trans. 95% of the time the dealer will just say its within specs or couldn't duplicate. Thats my humble opinion anyway, goodluck.