The Aurora, Ontario-based company now expects light vehicle production - its main measure for output of a diverse range of parts and assembly work - to reach 17 million units in North America, down from a previous forecast of 17.2 million.

The company also said it expects costs in its unit handling auto exteriors and structures to go up and total sales in fiscal 2018 to be between $40.3 and $41.4 billion compared to an earlier range of $40.3 to $42.5 billion.

North America's biggest auto parts maker, Magna is in the crosshairs of ongoing trade tensions, grappling with higher metal prices after the Trump administration levied tariffs on steel and aluminum imports, triggering retaliation.

In the quarter ending Sept. 30, light vehicle production in North America increased 4 percent.

Sales at its complete vehicle segment, which produces cars for BMW and Daimler, rose 48 percent to $1.4 billion but also showed the sharpest cut in the renewed outlook, down from $6.1-$6.5 billion to a range of $5.9-$6.1 billion.

Net income attributable to Magna rose to $554 million or $1.62 per share in the third quarter ended Sept. 30, from $512 million or $1.38 per share, a year earlier.

Excluding one-time items, the company earned $1.56 per share, while analysts on average had expected $1.51 per share, according to IBES data from Refinitiv.

Total revenue rose to $9.6 billion from $8.9 billion in the year ago quarter.

(Reporting by Arundhati Sarkar in Bengaluru; Editing by Patrick Graham)

By Arundhati Sarkar