These vehicles were given to people who pre ordered, but apparently there is no way to stop anyone else from getting them. Put these numbers into your phone and unlock some cool vehicles. Also for people concerned with having no cheats on their save game, these are not considered cheats.

Gyro Daddy helicopter (two person mini-helicopter) #4976
D-Stroy UFO (two person flying saucer) #728237
Peewee mini-bike (very small mini-bike) #7266837