My CPO '06 550i w/ 57k miles experiences an annoying, low speed shudder at about 20mph and 1000rpm in "Drive" when the car is cold. (Does not happen in "Drive Sport.") The dealer's shop foreman verified the problem and implemented a software fix under warranty called for under a recent BMW service bulletin (see below) which reduced the shudder but did not eliminate it. In response, the shop foreman had BMW's Regional Technical Engineer (RTE) drive the car (with my permission but w/o me there.) The RTE concluded that the shudder is a common issue with the tranny, that it happens under "unusual circumstances", that it does not impact drivability and that BMW does not believe that any further service is needed. The dealer says that it's the RTE's call and that it will tell me the next time the RTE is in the shop, so I can discuss it with him. (The RTE visits every couple of months or so.)

I have the following questions:

1. Does the dealer have no power in this matter?

2. Is the BMW Regional Technical Engineer (RTE) the one calling the shots?

3. Assuming it's the RTE's call, how can I convince him to fix it-- including a new tranny? (I am still waiting just to meet his highness.)

4. Given that the shop foreman thought that the shudder was a problem and that BMW issued a service bulletin and attempted a fix, BMW cannot now claim that it is not a problem and just give up, can it?

Here is the service bulletin: http://www.bmwtis.com/tsb/bulletins/bullet...mp/B240309g.htm

PS: The car has also experienced a harsh, slamming 2-1 downshift, but only once really bad.

Any suggestions to get BMW to fix it would be appreciated. Thanks.