Abstract: On August 3, 2009, Employee #1 was installing a new clutch box, weighing 400 pounds, into the clutch housing of a 52,000-lb tractor trailer. The truck had a front axle maximum vehicle weight of 12,000 pounds. Employee #1 used a 20-ton bottle jack to lift the front of the truck. By placing the head of the jack directly on the spring perch of the passenger side, the front passenger tire was 4 inches above the ground. He did not use a safety stand to maintain the elevation of the truck above ground. He then got on a snooper and positioned himself beneath the truck to align the clutch box with the clutch housing. Employee #1 used his left foot for leverage to maneuver the clutch box into place by placing his foot between the elevated passenger tire and the ground. While attempting to move the clutch box, the bottle jack slipped off of the spring perch, and the truck came down, crushing his left foot. Employee #1 was hospitalized for treatment.