I have a question regarding my 06 Scion XB. I just got it a couple of weeks ago, and have noticed from time to time that when my car shifts to the last gear, (it's a automatic) it sometimes does it at 60 mph and 4,000 R.P.M.s. It usually shifts to the last gear around 40 mph and 3,000 R.P.M.s. I don't acelerate very fast either. Is this normal for my car? Any suggestions would be helpful.