There was some interesting advice offered by two of our industry’s best-known economists last week to fleet executives who were attending the National Tank Truck Carriers annual conference in San Francisco.

Accelerating domestic demand pushed up first-quarter rail/truck shipments by 5.8% to 3.48 million, setting a record for the first three months of any year, the Intermodal Association of North America reported.

XPO Logistics reported a first-quarter loss and announced its first acquisition, saying it will buy brokerage firm Continental Freight Services for $3.4 million.

Heavy-equipment maker Caterpillar Inc. said it is selling a majority stake in its third-party logistics business to Platinum Equity for $750 million.

Logistics firm Expeditors International of Washington said its first-quarter profit declined from a year ago as air freight volumes fell.

New orders for trailers continued at a strong pace in March, despite dropping 30% from a year ago, ACT Research Co., Columbus, Ind., reported, adding that total orders for the first quarter were down just 1% from the strong performance in the first three months of 2011.