In order to meet tough new federal regulations that raise fuel economy requirements to 30 mpg for light trucks and SUVs by 2016, Ford is considering radical ways to reduce weight in the next-generation F-150, sources have told PickupTrucks.com.

In 2007, Ford CEO Alan Mullaly pledged to reduce the weight of all of the company’s vehicles by 250 to 750 pounds through the use of aluminum and high-strength steel. We’re told that Ford is considering replacing the F-150’s conventional steel-ladder-frame with an all-new platform featuring extensive use of an innovative magnesium-aluminum alloy to shed pounds.

Why magnesium? It’s 36 percent lighter than aluminum and 78 percent lighter than iron. It's also plentiful. Magnesium is the eighth-most-common element on Earth and highly recyclable.

Auto manufacturers have increasingly turned to magnesium over the last decade. BMW has used the material to lighten its engine blocks and the Chevrolet Corvette uses magnesium in its front suspension. Ford shaved 22 pounds of weight from the 2010 Lincoln MKT by combining separate aluminum and magnesium panels in the crossover's liftgate instead of using steel.

Frame stiffness is important in a pickup truck for towing and hauling; to ensure the alloyed frame can perform its job, the F-150 is expected to use limited elements of unibody construction, though the cargo box and cab will be separate, instead of joined as in the Honda Ridgeline. A similar approach, we're told, was considered for the shelved Ford F-100 program.

Beyond the frame, the future F-150 is also expected to use aluminum body panels to save weight over a steel skin. The interior of the cargo box is expected to still be constructed of steel, to retain the durability required of a pickup truck.

Ford has introduced three all-new engines for the 2011 F-150 that the automaker says give its half-ton pickup class-leading fuel economy. Reducing the truck’s weight is expected to further improve mileage, which could open the window to new engine opportunities that keep the power-to-weight ratio the same as the current F-150. Those engine choices might include an inline five-cylinder engine, a source said.