OK guys, I,ve got a 2004 300m with the 3.5l v6,109,000 miles. I just had a situation where around 50 mph the trans did not shift into 4th. when it happened my check eng.light came on,I pulled over and checked the code (0700)trans control module malfunction.Started it back up and drove it home using the autostick ,it shifted fine using all 4 gears. next day drove to work & back in drive(no problems ) as I got off expressway it down shifted hard and stuck in either 2nd or 3rd (not sure which!} then stopped at Advance Auto to check code 1776,reset codes and drove it home seems fine now! Any ideas? thanks for responses in advance!

Not to say this is your problem, but on those transmissions, the input AND output speed sensors will put the car into limp mode (stuck in 2nd)if either fails. They are fairly cheap and not hard (as I understand) to replace if this is your trouble.

Check ypur email sent you some info.
Kevin