It seems everytime I go over a hard bump or dip or the vehicle moves kinda hard, my reverse and/or brake lights don't light up and I have to smack the tail light to get the light bulb to turn on. This is really irritating it's almost everytime I hit the road that this goes on, it's like the sockets are sensative to movement? do I need new harnesses's?

 

If they all go out at once I'd check fuses and the ground connection. If it's one at a time, switching randomly, then I'd say the sockets aren't making a tight connection.