DaimlerChrysler has warned it could lay off up to 4,000 jobs at its North American truck operations next year.
DaimlerChrysler is the world's largest commercial truckmaker
The German-owned firm said the cuts - amounting to up to 16% of the truck division's workforce - would be the result of an expected drop in demand.
DaimlerChrysler's Andreas Renschler said possible job cuts would include 800 layoffs already announced for March next year, Reuters reported.
The firm's truck operations include US-based firm Freightliner.
DaimlerChrysler's truck division recently reported a record profit of $705m (£360m) during the third quarter of its financial year, up from $449m a year earlier.
But the company has warned that it expects to see an almost 40% drop in demand for large trucks in its key North American market over the coming year.
"Our challenge is to manage the cycles and to come through the down cycles while preserving profitability," Mr Renschler said.
DaimlerChrysler is the world's largest commercial truckmaker, and employs more than 25,000 workers at its truck operations in the US, Canada and Mexico.