I was driving on the Garden State Parkway in New Jersey in the right hand lane. I was using basic auto pilot and needed to pass a pick up truck in front of me. I disabled auto pilot and went into the left lane. I re-engaged auto pilot and the vehicle took a hard right and hit the truck. I heard the audible chime once it made contact with the truck indicating that auto pilot disengaged. My car went back into the left lane and I took control. We moved to the shoulder and waited for state police to arrive. Luckily no one was injured. A police report was filed.