Abstract: At 2:30 p.m. on September 4, 2003, Employee #1, an apprentice technician, was lying on a creeper under a moving truck diagnosing a problem. He unbolted the center section of the two-speed rear differential, pulled it out onto a hydraulic transmission jack, and wrapped the jack's holding chain around the pinion case to secure it. He then rolled the center section out from under the truck. While still lying on his left side on the creeper, Employee #1 turned the pinion with his right hand and held the case flange with his left hand. The ring gear, in contact with the transmission jack, turned and moved the differential section, which fell and crushed Employee #1's left hand between the mounting flange and the pavement. He was hospitalized for fractures to his index and middle fingers.