GMC gives a behind-the-scenes look at CarbonPro box production

A regular destructive test is performed on the GMC CarbonPro box at the Continental Structural Plastics plant in Huntington, Indiana. (Photo by Jeffrey Sauger for GMC)

Even once we left the plant floor, I could still hear the thunk, thunk, thunk of a sledgehammer as it struck against a crowbar.

Somewhere, two floors below the conference room in which I sat, a man was diligently trying to rip apart a GMC CarbonPro bedliner box, which had just come off the production line.

And he’ll do it.

It’ll just take several hours, according to plant manager Karen Williams.

Williams said this is part of the regular due diligence, and every day the Continental Structural Plastics plant runs the machinery that binds the pieces of the box together, they also do this destructive test.

“What better way to test the strength than to try to take it apart,” she said.

GMC is building its new CarbonPro box at the CSP plant in Huntington, Indiana, which is just down the street from the General Motors Assembly Plant in Fort Wayne where the GMC Sierra is built.

At the CSP plant, the CarbonPro box starts as sheets of shaved carbon fiber composite that get trimmed, pressed, stamped and trimmed again before all the pieces get bonded together.

Once a batch gets finished it’ll eventually get shipped over to the assembly plant where it will be placed into a 2019 Sierra.

Carbon fiber has long been used in racecars and expensive sports cars, so why use it in a truck bed?

Because, as Mark Voss, engineering group manager for GMC, put it: It’s the most corrosion, dent and scratch resistant box in the industry.

“It’s going to be cockroaches and carbon boxes when the world comes to an end,” Voss joked.

The GMC development team tossed cinder blocks, 1,800-pound loads of gravel and 450-pound steel water-filled drums in the back to see what would happen. They also did UV testing as well as exposed it to extreme temperatures from -22 degrees to 176 degrees Fahrenheit.

“The team tried everything they could think of to break this box, and they just couldn’t do it,” Voss said.

One guy even tried pound a hole in the bed with a baseball bat.

It didn’t end well for the bat.

Voss said they did the same testing on aluminum and steel boxes. The results? The steel boxes got dented, and the aluminum boxes got holes poked through the bed.

Outside of the durability, other features of the CarbonPro box include:

  • 14 fixed cargo tie-down hooks
  • a cargo lamp
  • tier loading
  • compartment divider
  • 110V power outlet
  • tire pockets for motorcycles

Additionally, by nature of the material, it creates a coarse grain on the top tier of the box, so there’s no slippage if you step in onto the bed.

Also of note, if you opt for the CarbonPro box, you’ll also get the MultiPro tailgate.

GMC hasn’t released any specific pricing specs or production numbers for 2019, but execs did confirm the CarbonPro box will only be available initially as part of a package on the Denali and AT4 trims, which will be called the CarbonPro Edition.

Additionally, GMC execs said the special edition pricing would be comparable to what the price would be if you check every box on one of these trims.

The most expensive Denali trim we could configure, without accessories or optional paint was just more than $70K, including destination and excluding discounts and cash allowances So, we estimate the initial price of this feature on a GMC truck to be right around the $70K mark.

The CarbonPro will have limited production for the 2019 model year, with wider availability starting in the 2020 model year.

Delivery of trucks with the new box will begin this summer.

The Bottom Line

The CarbonPro box is a really cool product that absolutely raises the bar on truck bed construction. The product is not only lightweight but also stronger than steel. It stands up to extreme temperatures, humidity and corrosive materials.

And it takes a guy several hours with multiple crowbars and a very large sledgehammer to take it apart.

While it will surely be an expensive addition, if you use your truck bed for hard labor, the CarbonPro box has the potential to pay dividends over the life of the truck since it likely won’t need repairs.