There is nothing in there that shows the parking pawl in an automatic transmission has been replaced by an electronically actuated 4 wheel parking brake, unless I'm missing it!

 

Ford Kuga AWD sliding when parked: http://youtu.be/ve7HAB24UqU

Can this be a clue?

Commenters on YouTube point to the tires. Occam's razor...!

 

Interestingly, my 06 XJ8 had an automatically actuating parking brake. My 07 XKR's has to be actuated manually.

 

Interesting video... and I only noticed the tires on the drivers side had in fact rolled, I didn't look at the passenger side to see if one of the other had slide. But even if one or the other did slide why didn't the 3 other cars that parked after me in my driveway slide? Sure tires may have something to do with it, but it still shouldn't cause it to slide when it didn't spin a tire pulling back into the driveway. I guess what I am saying is in 50+ cars and trucks that I have owned and about the same in Motorcycles (which I have long since stopped riding in snow) I have never had one slide after I parked it. And I have driven through some nasty conditions over the years.

Again as soon as it snows again I plan to chalk mark each tire to find out what is going on. Sadly the last 2 snows haven't been more than a dusting in in Cincinnati. And last winter I had 6 or 7 inches in my driveway when I parked and it didn't move. Nope the Jag does not get a nice parking spot in the garage, I have the 63 Mercury and 3 motorcycles in there and hopefully soon maybe a 46 Dodge

 

Yes you missed it from the BMW link "The parking Brake controls all braking processes whenever the vehicle is not moving".
I also know that the New MB S-Class has done away with the parking pawl also. As it was in it's press release, My post to this thread was not an effort to SOLVE the problem, only to possible help in a diagnosis... I'm moving on now!....lol

 

I would love to see the Mercedes press release you're referencing.

That being said, the OP's car does have a parking pawl. I suppose it's possible that the OP has a worn parking pawl, but I still don't know why it would roll only on snow and not dry pavement! And if it were broken inside the transmission there would be grinding noises when driving around town!

 

By the way, I was just doing some research and it appears older XJs and S Types had problems with parking pawls, but those usually manifested themselves as being stuck in park, not rolling down a hill.

 

That's a good point as the early S Type 1999-2002 do get stuck in park sometimes if parked on a incline. If you rock the car you can generally get it out of park.

The ZF 6 speed that came with the 2003 upgrade does not seem to have that problem.
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