That`s normal. when you jack up a car and then let it down, the weight dosen`t settle all at once. You can see another example of this, if you take a sharp turn and immediately stop the car. the weight transferes to the opposite direction of the turn. If you make a sharp turn to the right and stop the car will lean to the left. As soon as you move the it levels out. This is because the weight transfered,but by stopping the motion and energy stops and the car takes a "set".This is especialy noticable if the car is traveling down/up hill just before the turn.