I have an automatic 2003 GTS. I recently noticed that when I slow down it doesn't shift down from 4th gear. Is this normal or is there something wrong? I have also noticed a low hum once I reach a higher speed. I was thinking that it might be my transmission. I had my car parked while the car was on and when I put it in drive it would not go forward even as I gave it gas. The engine did not rev as I stepped on the gas. The car did not move until I put it in M mode that it started to move and I was able to drive the car home. But once I got it home and restarted the car it was working again without having to be in M mode. Has anyone had this problem or know what is wrong with my beautiful car? Please let me know...
