Propelled by stronger sales in its core business and military unit, Navistar International (NAV) reported Wednesday a stronger-than-expected fourth-quarter profit. 

The Warrenville, Ill-based company posted net income of $39 million, or 54 cents a share, compared with $86 million, or $1.19 a share, in the same quarter last year.

Excluding one-time items related to layoffs, the company earned 68 cents a share, ahead of average analyst estimates polled by Thomson Reuters of 60 cents.

Revenue for the manufacturer of commercial trucks, buses, diesel engines, military vehicles and chassis for motor homes was $3.37 billion, up from $3.29 billion a year ago, beating the Street’s view of $3.21 billion.

Its truck segment led the gains, up to $424 million compared with $147 million a year ago, aided by improvement in commercial markets, and in spite of 50-year industry lows.

“The North American truck market has been depressed for three years now and the company has been able to provide good profits while investing in the future growth,” said Navistar CEO Daniel C. Ustian. “The company is well positioned to take advantage of the growing North American market as well as expanding globally.”

Navistar invested more than $55 billion in global expansion this year and said it believes it will deliver profits by fiscal 2011 and provide solid returns to its bottom line in 2012 and 2013.

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