General Motors will cease production of its Chevrolet Express and GMC Savana 1500 full-size vans after the 2014 model year as the automaker turns its attention to more fuel-efficient models.

The 1500 series Express and Savana offered for the 2014 model year will be the last full-size vans offered by GM with a gross vehicle weight of less than 8,500 pounds. Light-duty vehicles, including full-size vans, weighing at least 8,501 pounds are exempt from federal Tier 2 emissions requirements.

GM will cease production of the vehicles this summer, said Robert Wheeler, a spokesman for GM's fleet and commercial unit.

Many of our customers have converted to the 2500 series vans with 4.8L engine mated to a fuel efficient six-speed transmission, and we expect the 2500 series van to be a value leading van in the market place for the 2015 model year," Wheeler told AutomotiveFleet.com.

GM will offer the heavier 2500 and 3500 models of the Express and Savana beginning this summer. The 2500 series weigh 8,600 pounds, while the 3500 series weigh 9,600 pounds with the 6.0L gasoline V-8 and 9,900 pounds with the Duramax 6.6L diesel V-8.

The 2500 and 3500 will be available in several configurations including a cargo van, cutaway, and passenger model seating eight, 12, or 15.

For the 2014 model-year, the 1500 series Express and Savana weigh 7,300 pounds, which qualify them for Tier 2 emissions standards. The rear-wheel-drive Express 1500 cargo van with a 4.3L V-6 gets an EPA-rated 14 miles per gallon city and 19 mpg highway. The same van with a 5.3L V-8 gets an EPA-rated 13 mpg city and 18 mpg highway.