Recently I sold an 82 240D,auto trans , and got an 87 300SDL. The transmission in the SDL has a different feel,not just because it's new to me. If I'm parked on a slight incline,when i put it into "D",car will roll backwards until I give it gas.Shouldn't it, being in a forward gear,even without giving it fuel,at least stay in place,or even go forward a little?I know the 240 would either hold or go forward.Is this a problem or bad sign? Likewise,on level ground,shouldn't it go forward if it's in "D"just on the power of the idle,without hitting the pedal??Any and all advice will be appreciated.