UPDATE 2-Cummins keeps earnings forecast unchanged, shares fall

* Q2 EPS $2.53 vs est $2.58

* Raises full-year revenue outlook

* Expects EBIT of 11.75-12.5 pct of sales (Adds details, analyst comment, updates shares)

Aug 1 (Reuters) - Cummins Inc's shares fell about 5 percent after the U.S. engine maker's profit missed Wall Street estimates and the company kept its 2017 forecast for earnings before interest and tax (EBIT) unchanged, despite raising the revenue outlook.

Cummins, which counts PACCAR Inc, Daimler AG and Navistar International Corp among its customers, said it expected 2017 EBIT to be in the range of 11.75 percent to 12.5 percent of sales.

The Columbus, Indiana-based company, however, raised it 2017 revenue growth forecast range to 9 percent to 11 percent, from 4 percent to 7 percent, previously.

Analysts on average were expecting full-year EBIT at 11.9 percent of sales, and revenue growth of 5.5 percent, according to Thomson Reuters I/B/E/S.

An increase in earnings in the quarter was partially offset by higher warranty costs that resulted in second quarter EBIT that was below the company's expectations, Chairman and Chief Executive Tom Linebarger said in a statement.

Cummins said its EBIT fell to 12.2 percent of sales in the second quarter ended July 2, compared with 13.1 percent, a year earlier.

"Segment incremental margins in the low single digits is disappointing even as oil and gas and mining related activities picked up in the quarter," Jefferies analyst Stephen Volkmann wrote in a note.

Cummins, which provides engines for large trucks that haul a majority of U.S. freight, said revenue from North America, its biggest market, increased 13 percent, in the quarter.

Pick-up in orders for heavy-duty trucks, whose production had fallen in the United States due to a supply glut, is helping Cummins' sales growth in 2017.

The company said its international sales grew 11 percent in the quarter due to strong demand in China and India.

Net income attributable to Cummins rose to $424 million, or $2.53 per share, in the second quarter ended July 2, from $406 million, or $2.40 per share, a year earlier.

Net sales rose 12.1 percent to $5.08 billion.

Analysts on average expected second-quarter earnings of $2.58 per share on revenue of $4.80 billion.

Cummins' shares were down at $159.75 in premarket trading.

Up to Monday's close, the company's stock had risen about 22.9 percent this year, compared with a 17.7 percent increase in the Dow Jones U.S. Commercial Vehicles and Trucks index . (Reporting by Ankit Ajmera in Bengaluru; Editing by Arun Koyyur)