Truckload carrier P.A.M. Transportation Services said Wednesday its second-quarter profit declined from a year ago.

Ryder System said Wednesday its second-quarter profit increased from a year ago and raised its earnings forecast for the rest of 2011.

Norfolk Southern Corp.’s second-quarter profit jumped 42 percent from the same quarter last year, the Eastern freight railroad reported.

Saia Inc. said Wednesday its second-quarter net income rose from a year ago on higher revenue, improved pricing and increased tonnage.

Canadian National Railway Co. said its second-quarter net income rose to C$538 million, or C$1.18 cents per share, from C$534 million, or C$1.13 per share, a year earlier.

Transportation and third-party logistics firm C.H. Robinson Worldwide reported a second-quarter profit of $111 million, or 67 cents a share, up 14.2% from $97.2 million, or 59 cents, a year earlier.

Qualcomm Inc., a maker of trucking communication devices and wireless chips, said fiscal third quarter income rose to $1.03 billion, or 61 cents per share, on revenue of $3.62 billion.

Six of seven publicly traded large truckload carriers delivered strong second-quarter profit increases last week, as capacity constraints helped to boost rates and margins.

YRC Worldwide Inc. expects to earn its first profit from operations since 2007 in the second half of 2011, the less-than-truckload carrier said.

Heavy equipment maker Caterpillar Inc. said Friday its second-quarter profit jumped 44% on higher sales, despite extra expenses from the company's acquisition of Bucyrus.