Revealing mistake: When the trucks start circling the Dixie Boy the blue truck turns in front of the orange Bic truck if you look real close you can see a hand on the steering wheel turning the blue truck. (00:15:00)
Revealing mistake: When the ice-cream van is being shot at the end of the film, for a single shot you can see the driver sitting in it.
Revealing mistake: After Hendershot blows up the two trucks, Brett runs into the door. It's very obvious the glass was removed and replaced with plastic because it makes a plastic sounding noise and wobbles.
Revealing mistake: During the scene where Curt and Connie stop at the gas station, When Curt jumps to avoid the tow truck, you can see the dead gas station attendant (or possibly a crew member) laying down. When the truck skids to a stop you can briefly see him get up and move around behind the bushes to the left.
Revealing mistake: At the end of the movie when the survivors are sailing on the boat, the guy piloting it is Steve's stunt double because he has straight hair and is a completely different actor. In the next shot it's Steve piloting the boat.
Revealing mistake: During the bridge scene when the gray van crushes the red Chevette, if you look to the right of the screen a dummy is visible in the ACDC van.
Revealing mistake: When the trucks start circling the Dixie Boy the red garbage truck hits a telephone booth. A human arm is visible, you can also see an arm in the orange Bic truck when it cuts into the blue 15 truck.
Revealing mistake: When the red Autocar garbage truck hits the bible salesman's car, you can see a harness holding the two front tires in place for the truck to make the car fishtail.
Revealing mistake: When Hendershott is shot after shooting the bulldozer, you can see the blood packs used under his shirt.
Revealing mistake: When the lawn mower starts itself and tries to pursue Deke, from the back, the front wheels are on the ground and rolling. From the front angle, the front wheels are off the ground. There is a piece of material on the front that was added to hide the steering rig used to make it turn to chase Deke, but the rig's wheels are just visible.
Revealing mistake: When Curtis and Connie attempt to get into the Dixie Boy their stunt doubles are visible.
Revealing mistake: When the Miller beer semi hits the car the second time, you can see the truck's exhaust stack isn't connected.
Revealing mistake: In the shot after the motorcyclist falls into the water, the camera shakes and you can also see something lifting the cameraman up.
Revealing mistake: After the waitress gets cut with the knife, she leans on the grill, it makes a sizzling sound and yet she doesn't get burned.
Answer: The Pinball Machine overloaded at speed.