When it is extremely hot or extremely cold, anything under or over 50 or 60, my car will jerk very hard when accelerating. Also while in reverse, the car will not move and if your on a hill, you almost roll right into the car behind or in front of you. I have heard it could be low transmission fluid or clogged filter or the tires need to be aligned. Where I live no one knows much about the car and is extremely expensive to fix. What possibly could be wrong?