Cummins reported sharply higher sales and earnings compared to the first quarter of 2010 on continued strength in key international markets, a recovering North American truck market and productivity improvements.

First quarter sales of $3.9 billion were up 56 percent from $2.5 billion in the same period in 2010. Earnings before interest and taxes were $532 million, or 13.8 percent of sales, double the company's earnings from the same period a year ago. EBIT as a percentage of sales in the first quarter was at its highest level in at least 25 years.

Net income attributable to Cummins was $343 million, $1.75 per share, compared to $149 million, 75 cents per share, in the first quarter of 2010.

As a result of the company's performance in the first quarter and its forecast for the remainder of the year, Cummins increased both its EBIT and sales guidance for 2011. The company now expects to earn 14 percent EBIT on $17 billion in sales in 2011.

Engine segment sales of $2.4 billion were up 68 percent compared to the same quarter a year ago, which was artificially weak due to a change in emissions standards and the economic downturn. Segment EBIT of $290 million, or 12.1 percent of sales, was a quarterly record.

Engine shipments in the global heavy-duty truck market more than tripled year-over-year, while medium-duty truck engine shipments increased 114 percent. In addition, shipments to global industrial markets such as construction, up 60 percent, and mining, up 59 percent, also were strong.