The shifting problem sounds like a bad shift solenoid. As far as the noise, do you hear it when going over bumps?
As far as the maintenance, the manufacturer does have a schedule. However, even with that, you don't know when anything was done. What I recommend is this, check the fluids. Make sure they are clean and full. The transmission should be a redish pink color. PS fluid is more of a light gold color and nearly clear. I would suggest haveing everything serviced. That way you know when it was done and can move on from this point.
Let me know about the other questions.
Thursday, August 5th, 2010 AT 10:25 PM