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Jan 14 (Reuters) - Canada's Magna International Inc , one of the world's largest auto parts suppliers, forecast a surprise fall in fiscal 2015 revenue, hurt by falling sales in its production and contract manufacturing businesses.
Magna said it expects total revenue of $34.4-$36.1 billion for the year.
Analysts' on average were expecting sales to rise to $37.7 billion from the company's estimated sales of $35.8-$37.0 billion in 2014, according to Thomson Reuters I/B/E/S.
Magna forecast total production sales, its core business of manufacturing vehicle parts, to slip to $29.2-$30.5 billion in 2015 from expected sales of $29.8-$30.7 billion last year.
Sales in its contract manufacturing business is expected to fall to $2.4-$2.7 billion in 2015 from $3.1-$3.3 billion forecast for fiscal 2014.
Magna, which has been pushing to improve efficiency in its European operations, counts the world's top automakers such as General Motors Co, Volkswagen AG, BMW and Ford Motor Co among its customers.
The company said it expects operating margin to be in the low 7 percent range next year, higher than estimated margins of about 6.9 percent for 2014.
Magna expects capital spending of $1.5-$1.7 billion in 2015, more than the estimated 2014 capital budget of about $1.4 billion.
Aurora, Ontario-based Magna's shares closed at C$123.24 on the Toronto Stock Exchange on Tuesday, while its U.S.-listed shares closed at $102.99. (Reporting By Shubhankar Chakravorty in Bengaluru; Editing by Savio D'Souza)