2019 GMC Sierra gets optional carbon fiber cargo box

The CarbonPro option will initially be available on two trim levels.

After criticizing rival Ford for manufacturing the F-150 using aluminum, GMC announced it's putting the Sierra on a diet by adding a cargo box partially made out of carbon fiber to the list of options. The weight-saving feature will be available on select trim levels starting in the summer of 2019.

The firm explained it developed the carbon fiber box to make the Sierra lighter, stronger, and more durable. The CarbonPro box weighs about 60 pounds less than a conventional steel box, which represents a 25-percent mass reduction, and it gives the truck one additional cubic foot of cargo capacity. Buyers who order the option will be able to haul at least 59 pounds more, according to GMC.

GMC carved three indentations into the box to help users load dirt bikes and ATVs in the back of the CarbonPro-equipped Sierra. Numerous tie-down hooks integrated into the bed side help owners secure anything they need to haul. The carbon fiber doesn't rust, it's scratch-resistant, and it withstands extreme temperatures on both ends of the thermometer. GMC tested the box by dropping cinder blocks, 450-pound water-filled steel drums, and 1,800-pound loads of gravel into it.

Only the inside of the box is made with carbon fiber. The outer panels are manufactured using steel. Sierra models equipped with the CarbonPro option look fully stock with the exception of an option-specific emblem on both fenders.

Buyers who want a basic, work truck-spec Sierra with the carbon fiber box are out luck for the time being. The option will be available on the Denali 1500 and the AT4 1500, two of the more expensive members of the Sierra line-up. It will be an option, but GMC hasn't revealed pricing information yet. The company noted the carbon fiber liner will be offered on more trim levels for the 2020 model year, and it's reasonable to assume the feature will spread to the Chevrolet line-up sooner or later.