Share 'Drive train parts examined in deadly monster truck accident - Metal chunk struck 6-year-old boy in head'

P-I STAFF AND NEWS SERVICES Investigators examined pieces of the drivetrain from an oversized truck this weekend to try to learn why a Frisbee-sized chunk of metal tore loose and killed a 6-year-old boy at a Monster Jam truck show in the Tacoma Dome. "Natural High," the so-called monster truck at the center of the investigation, appeared to have mechanical problems Friday night before it spewed m…