My husband did a tranny service on our 2005 impala, which has very high miles, and since doing that, he has to shift into second gear to take off then manually shift up to drive. If you put it into drive, and try to take off, it is like the car is a neutral. It will not move unless you shift down to second. It had hard shifting prior to the tranny service. But never this issue. Any suggestions as to what might be the problem