Lisle, Ill.-based Navistar (NYSE:NAV) shares took a big tumble Wednesday, falling more than 5% in reaction to a fiscal Q3 2013 earnings report that featured a per-share net loss more than twice as much as had been feared, and a revenue disappointment to boot.

Navistar reported total revenue for the quarter of $2.9 billion, down 12% year over year, and just shy of analyst estimates of $2.92 billion. The bigger problem was earnings, or rather the lack of them: $3.06 per diluted share in Q3, a 151% increase over last year's losses, and more than twice the $1.32 loss that analysts had warned of. Losses from discontinued operations accounted for only $0.12 of the total loss.

Navistar management attributed the difficulties to "lower volumes in its core North America truck business due to the impact of the company's transition to [selective catalytic reduction]-based products and weaker industry conditions."

Moving to cut costs in response to the weak results, Navistar revealed last month that it is in the process of laying off 500 salaried employees and long-term contractors globally. Navistar expects to complete the layoffs this quarter and hopes to reap $50 million to $60 million in annual savings starting beginning next quarter, the first quarter of Navistar's fiscal year 2014.

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