Quicksilver,

Thanks for all that info! My wife's 05 has had this problem for a few months now, but it's now beginning to happen more often. Several times she's thought she was just rear-ended. It finally happened with me driving a few days ago. It is a very forceful thud and sudden lurch forward. My impression is that it seems like the transmission is slipping (violently) when down-shifting from 2nd to 1st gear.

Here are my other observations of when this seems to occur:

- Going uphill or a slight upward incline
- Slow down to near stop, then let off the brake and apply the gas lightly

A perfect is example is when my wife pulls into our garage, as our driveway has a slight upward slope. This sudden and violent jerk of the whole car forward has occurred at least twice when her car has pulled into the garage.

I would think BMW NA would be very concerned about this as I can see some ambulance chaser attorneys pursuing lawsuits against BMW NA if someone were to get whiplash or run into another vehicle or object as a result of this.

Perhaps BMW should be reminded of the sudden acceleration class action lawsuit (and subsequent recall) in the U.S. a few years ago - I believe it was against either Ford or GM for vehicles that would suddenly accelerate forward without any action by the driver.

RR