Caterpillar (CAT -4.6%) leads the DJIA lower (-0.8%) after Cummins slashes its 2012 outlook. Joy Global (JOY -6%) tumbles as well. The XLI -1.8%. More from Cummins (CMI): "Order trends in the U.S. for trucks and power generation equipment have softened and demand in Brazil, China, and India is not improving." Ouch.