In July, the good old boy contingent was horrified to hear that Ford would contemplate building Ford tough trucks from a material considered good enough for beer cans: Aluminum. Now, they will be absolutely terrified by the news that GM wants to build trucks from a material known to treat heartburn: Magnesium.
It’s all for putting trucks on a weight-loss diet in order to meet fuel economy requirements. Magnesium is 75 percent lighter than steel and 33 percent lighter than aluminum, GM engineer Paul Krajewski told Reuters. Magnesium also costs three to four times as much as aluminum.
The stiff space-age metal is a bitch to work with. Usually, magnesium parts are formed by high pressure die casting. GM developed a way to stamp parts from magnesium sheet metal. Still, the process is slow and complicated: The sheet metal must be heated to 842 degrees Fahrenheit before stamping.
By 2020, magnesium will be able to take out 15 percent of the weight of a vehicle, leading to fuel savings of 9 percent to 12 percent, Reuters says. GM is just at the beginning. It’s first use for stamped sheet metal magnesium is a rear deck lid inner panel. Weight savings: 2.2 pounds. And you need to be very lucky to get a magnesium-enhanced truck. GM will make about 50 vehicles, which will be sold to consumers, using the magnesium sheet process in the fourth quarter, but nobody is telling which models will be graced with the space-age parts.