A toy vehicle includes a supporting chassis (12) having a plurality of rolling wheels (13, 14, 15, 16) secured thereto. The chassis supports an audio circuit (61), a battery (62) and an audio transducer (60) together with a pair of switch contacts (52, 53) configured to provide a growling sound when the switch contacts touch. The chassis further supports an articulated body (11) having a cab portion (30) and rear portion (31) resembling a standard truck joined in a pivotal attachment. A shaft (40) and cam (51) mechanism is coupled to a movable arm (43) in a cooperative arrangement in which pivotal motion of the movable arm closes the switch contacts activating the audio circuit and raising the cab (30) and rear portion of the truck body to expose sets of hidden teeth (22, 23) at the front of the toy vehicle.