One problem related to automatic transmission floor shift has been reported for the 2004 Nissan Titan. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Nissan Titan based on all problems reported for the 2004 Titan.
While backing my boat into its parking spot I put my vehicle in "park", left the driver's door open, left engine running and exited vehicle to unhitch my boat trailer from my truck trailer hitch. I was at the rear of the vehicle turning the trailer jack. I was behind the truck for approximately 45 seconds when I heard a click, and my vehicle started moving backwards. I realized what was happening--the gear shifted from park to reverse. I attempted to enter the driver's side,and opened door to hit the brake. While entering the driver's side I was holding onto the door as leverage attempting to apply my right foot onto the brake pedal. The reverse movement caused the door to come in contact with a tree. The tree pulled the door forward as the vehicle was moving backwards. The door's contact with the tree caused the door to pull me out and threw me to the ground, causing injury to my left arm and leg. I got up and ran and jumped into the cab of the truck and was able to stop the vehicle. Supposedly being investigated by Nissan technical representative.