I am the lucky winner of an X5 that does this. I'va only had the car since last weekend, I bought it from a local stealership. Clean Carfax, only 66k miles, cherry. Of course, my
only test drives were after the dealers had started it and driven it, so I was getting the car already warm each time.

The first day after I bought it, I pulled out of my driveway and put it in drive, and the engine just spun up like I was in neutral....I figured as a newbie owner I didn't shift it all the way or something, so popped it back into park then drive again and it took off. I spent a good chunk of the rest of the day trying to reproduce it, and failed, so I thought all was well until the next morning when it did it again, and I knew something was up.

After researching the forums, I found the BMW TSB on it that my tranny is out of spec and needs between 5 and 30 seconds to pressurize on first use daily. It could have been fixed under warranty if the previous owners had caught it in time. I am sure the stealership knew of the problem, they probably figured the trans was starting to go, which explains the good deal I got. They took my first offer, lol

Anyway, now that I know what I am dealing with, it's all good. I just start the car, step on the brake and drop it into drive, and wait for about 30 seconds (fiddle with my radio, check my phone, etc) and THEN reverse out of my garage and go on my way. I really love the X5! Maybe down the road I'll swap out the tranny but for now it's not a big deal.

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2003 X5 3.0I, Titanium Silver Metallic, 70k Miles