I have an automatic trany. for example. When a car is in front of me and is going to turn I have to slow down and then when they turn I push the throttle but the trany slips and revs high and then kicks in. It seems like it is slipping, But it only does it if I stop real fast or turn a corner real fast or too sharp. It doesn't hardly do it any other time. It seems to shift fine. What could it be. Trany needs rebuilt????