Trailer manufacturer Wabash National Corp. reported a second-quarter profit compared with a loss a year ago, as trailer sales improved.

CSX Corp. late Tuesday reported record second-quarter earnings, as its profit rose to $506 million, or 46 cents per share, from $414 million, or 36 cents, a year ago.

Orders for new trailers in May increased 30% from a year ago but slipped from an April peak, although manufacturers said the market remained strong, with total orders through May 77% ahead of 2010 and with a growing backlog of deliveries.

The Pennsylvania Department of Transportation has approved two stretches of state highway for use by wider truck trailers.

The average price of a gallon of diesel fuel the week of June 6 was 18% higher than it was at the beginning of this year, according to the U.S. Energy Information Administration, and the June 6 price of that fuel in California was 20% higher.

Commercial trailer producers received 19,579 new orders in April, a 71% jump from the same month last year, and the manufacturers’ backlog rose above 100,000 for the first time in the current recovery, ACT Research Co. said.

Trailer Bridge Inc.’s first-quarter loss widened to $10.4 million, or 86 cents per share, compared with a loss of $300,00, or 3 cents, a year ago.

Both orders and factory production of new commercial trailers more than doubled in March, compared with the same month of 2010 and leading to escalating prices and longer wait times, industry officials have said.

Trailer manufacturer Wabash National Corp. reported a first-quarter profit on improved sales, turning around a loss from a year ago.

North American Trailer said it has acquired Fontana, Calif.-based Quality Fleet Repair, effective Sunday. Terms were not disclosed.