Directed by: Ron Underwood
Starring: Kevin Bacon, Fred Ward, Michael Gross, Finn Carter
Visible crew/equipment: Look over Val's right shoulder as Rhonda is supposedly driving upside down with her legs sticking out the back window of the truck cab and you can see a man driving for her. (00:42:40)
Continuity mistake: When they are picking up Burt and Heather, Burt throws a sack to Val. When it cuts Val catches a totally different sack. (01:15:07)
Revealing mistake: Near the end, Val, Earl and Rhonda are way off the rocks after the blast. When the monster comes up out of the ground and Val takes off, you can see the "ground" bounce. It's definitely a false ground so they can get the "graboid" pushed up through it. (01:24:10)
Chosen answer: The machine is a vibrating case cleaner, which is used to polish the brass casings of pistol and rifle ammo. The "dirt" is actually an abrasive polishing compound.
BGraz