It's long been known that aluminum is an effective way of reducing the weight of vehicles, but Ford's adoption of the metal for its 2015 F-150 truck has finally spurred others into action in the pickup class too.

General Motors has recently secured contracts with aluminum suppliers Alcoa and Novelis Inc so it can produce its own aluminum-bodied truck.

According to The Wall Street Journal though, it won't arrive until around late 2018--giving its rival Ford a hefty head-start in the market.

For some automakers, aluminum is the most effective way of improving the efficiency of large, heavy trucks, and one of the most effective way to meet stricter future fuel efficiency targets.

Use of aluminum has cut several hundred pounds off the weight of the new F-150, not only useful for efficiency improvements but also to the benefit of acceleration and braking performance and vehicle handling.

MORE: 2014 Pickup Truck Gas Mileage: Ford Vs Chevy Vs RAM, Who's Best?

Lighter bodies can also allow the use of smaller, lighter engines, in a virtuous circle for efficiency. The 2015 F-150 offers a 2.7-liter six-cylinder powerplant as one of its engine choices, much smaller than the norm in such vehicles.

GM has been slow getting the aluminum truck off the ground as until Ford's arrival, it wasn't sure whether such a vehicle could be cost-competitive, or even appealing to customers.

The firm had considered aluminum Silverado and Sierra models as far back as 2008, before the economic downturn put a stop to any discussions. GM says it restarted aluminum talk before Ford displayed its aluminum F-150, though now it has some catching up to do.

MORE: Why Green Car Reports Writes About Full-Size Pickup Trucks

In the meantime, the company will introduce component upgrades to the range, similar to Chrysler's plan with RAM trucks--which have adopted high-efficiency axles, 8-speed auto transmissions and a range of new gasoline and diesel engines.

GM is expected to introduce a 10-speed automatic--co-developed with Ford--to the Silverado range in 2016. The transmission will also appear in the F-series around the same time.

There are still some downsides with the new aluminum bodies--they're no longer quite as easy to repair as steel is--but for pickup trucks they're the new low-hanging fruit of greater efficiency.

_________________________________________

Follow GreenCarReports on FacebookTwitter and Google+