[shadow191]

Handbrake only locks the rear. Putting the car in P will lock the rear as well. There is literally a pin that locks the transmission together when engaged. But the front driveshaft is disconnected so the front can roll. But the same thing happens with a RWD car in Park, the rear tires would be locked and the front free to roll.

Seems like your problem is ice. Wheel chocks may be the only sure solution.

Originally Posted by adidoman

So it snowed enough last night to do a little text. I marked chalk on the wheels and lines in the snow and when I was taking pictures the car slid down right in front of me. The rear tires locked up and were sliding down while the front moved.

I tried the test again this time really cranking up on the handbrake and it still slid down, same results taking a little longer this time. I would think the handbrake would stop the front wheels from rotating, or am I wrong?

[adidoman]

Originally Posted by ajsalida

Did the 1 series have same type of tires?

edit: btw I don't think any AWD car/suv locks up the transfer case in Park. And no 4wd (like a pickup) would unless it is left in 4wd. However the BMW is basically a RWD car with a TC tacked on. In Park the dominant wheels are locked up, in this case rears leaving front to spin freely. In a FWD dominant AWD car, like many Audis, the front axle will lock up in Park, but the parking brakes in either FWD or RWD will still be the rears. So an Audi may appear to lock all 4 wheel in park with the e-brake on, but in reality front is locking from the tranny and rear is the brake. Without the brake rears would roll freely.

I had very crappy summer performance run flats on the 1er and it never slipped down, but I only had those on for a very short while when the snow came