Ttruck maker Paccar has reported a strong increase in third-quarter sales and revenue but said gross margins fell sequentially amid rising commodity costs, according to CBS Marketwatch.

The company reported third-quarter earnings of $US246.7 million, or $1.41 a share, up from $132.5 million, or 75 cents, in the year earlier period as revenue rose 42% to $2.92 billion, due mostly to solid economic growth in North America and a strong vehicle replacement market.

Wall Street expected earnings of $1.36 a share, on average, with sales of $2.6 billion, CBS Marketwatch said, citing Thomson First Call.

Analysts, for the most part, reportedly lauded results but said that gross margins were weaker than expected.