I have E46 330xi, have had it for over three years and I live in Canada where it is often -20 degrees celsius in the winter. It was rather warm yesterday, nearly 10 degrees celsius here and I took the car to the drive-thru soft cloth car wash. The undercarriage of the car was washed as well. When I started the car this morning, everything was fine. But when I put the car in reverse to get it out of the garage, it made a pretty loud sound and it felt as though one of the car's wheels was going over a speed bump or curb.

In the past, I've encountered problems with getting the car into reverse the morning after a wash. The car just would not move, I would have to give it gas and then it'd make a loud noise and the wheels would act like it was climbing a curb before the car would reverse. Has anyone who live in cities with harsh winters ever had this problem?

 

Were the brakes wet when you parked it? Might have had a thin film of rust on the rotors binding the calipers or part of the brake mechanism might be rusting in the "on" position somehow resulting in it not releasing properly when you release the hand brake. Needs to overcome some resistance before the brake pops back into its normal position.

 

that was most likely the problem...you parked it while wet causing the line rusty lining keeping the brakes in place

 

Does this really affect the brakes? Everything goes back to normal after the hiccups when I try to reverse.

 

Should be the parking brake. Rear brake shoe and drum probably 'fused' due to rust. Therefore there was a thud when you put to R or D