COLUMBUS, Ind. (AP) -- Cummins Inc. third-quarter net income jumped 60 percent on strong sales of engines in North America and Latin America, the company said Tuesday.Although the results were well ahead of Wall Street estimates, the company trimmed its full-year revenue estimate due to uncertainty about the global economy. Cummins shares fell $6.27, or 6.3 percent, to $92.55 in premarket trading.The Columbus, Ind., company earned $452 million, or $2.35 per share, during the quarter, compared with $283 million, or $1.44 per share, a year earlier.Revenue rose 36 percent to $4.63 billion.Analysts polled by FactSet expected earnings of $2.26 per share on revenue of $4.63 billion.Cummins, which makes diesel engines and power-generation equipment, said sales at its engine segment jumped 43 percent to $2.96 billion with more trucks on highways in North and Latin America. It also reported strong oil and gas mining engine sales worldwide.Power generation sales were up 10 percent to $874 million on growth in China, North America and Europe, partially offset by weaker demand in India and Latin America.Component sales rose 32 percent to just over $1 billion, driven mainly by highway truck markets in the U.S. and stronger growth in emerging markets, the company said.The company trimmed its full-year revenue forecast to a range of $17.5 to $18 billion. In the second quarter, it had raised the forecast to $18 billion. Analysts expect just over $18 billion in revenue for the year, according to FactSet."There is some uncertainty around the macroeconomic environment," Chief Operating Officer Tom Linebarger said in a statement. "Government actions to reduce inflation in India and China have resulted in softer near-term demand than we previously expected." He also said the recent strengthening of the dollar influenced the decision to cut the revenue projection.