Originally Posted by mejim707

Update 2:

I removed the underside cover and unplugged the transfer case actuator motor harness. I drove the car without the transfer case engaging the front wheels and what do you know, the entire car feels brand new. Zero shudder, zero coasting shake and no more fluctuation while braking. This is 100% certain that the transfer case is the issue.

As mentioned, I have a "new to me" transfer case going in Monday or Tuesday. It takes about 2 hours max to do the job.

BMW Dealer quoted me $8500 for this, and they are trying to charge 9 hours labor.

But you know what, they did diagnose the issue and didn't charge me for the visit so they were honorable about what they did do.