In a first for any production pickup truck, the all-new 2019 GMC Sierra will offer a carbon-fiber composite bed that GMC promises will be lighter and tougher than a conventional steel bed.

Other updates include a multiposition tailgate that can be used as a step or a seat, and technology that improves driver visibility and makes it easier to tow a trailer.

There's also an all-new trim level—called AT4—that mixes the luxury appointments of a Denali with off-road extras. While it debuted on the Sierra, GMC has plans to roll out the AT4 trim across its vehicle lineup.

GMC first took the wraps off the redesigned truck at a special event in Detroit on March 1, but the truck company waited until an event ahead of the New York Auto Show to show off the AT4. 

2019 GMC Sierra

What it competes with: The Ford F-150, Ram 1500, and Chevy Silverado (with which it shares a design and engines).

What it looks like: An urban cowboy—tough, but with a luxe trim.

Powertrains: 5.3-liter V8 (base), 6.2-liter V8 (optional), 3.0-liter diesel six-cylinder (optional).

On Sale Date: Fall 2018

2019 GMC Sierra AT4
2019 GMC Sierra AT4

Outside

The Sierra has a lot in common with the 2019 Silverado, which debuted in January in Detroit. However, the Sierra's new look is unique. GMC says the vehicle’s taller hood and grille give it a “more dominant” appearance, and the overall look is similar to that of the Terrain SUV, down to the C-shaped headlights. The AT4 gets a suspension that's lifted by 2 inches, vertical tow hooks, and black chrome accents.

GM claims that the use of aluminum doors, hood, and tailgate save up to 360 pounds over the outgoing model. Still, the new Sierra is larger than the current model in almost every dimension, which translates to more interior storage and 3 inches more rear legroom in crew-cab models.

The optional CarbonPro bed replaces the standard steel inner panels and floor with a purpose-designed carbon-fiber composite, which GM says saves 62 pounds compared with the current truck. (The rest of the box is made of steel, fiberglass, and aluminum.)

In its press release, GMC says the bed offers improved dent, scratch, and corrosion resistance. It will be available only on the Denali and AT4 trims. GM and Ford have sold trucks with plastic composite beds before, but this marks the first use of high-strength carbon fiber in a pickup. 

GMC’s new MultiPro tailgate is standard on the Denali, Sierra SLT, and AT4 trims. (GMC has not yet shared details about other trim levels.) This tailgate offers six positions, including a “standing workstation” mode that folds the top half of the tailgate down, like a desk. It can also be used as a step or a seat, and it can hold up to 375 pounds.

The AT4 comes with standard four-wheel drive, a two-speed transfer case, a locking rear differential, and skid plates. 

Inside

From the driver’s seat, the interior of a base Sierra looks a lot like the Silverado—but only the Sierra offers the optional Denali trim, which adds unique leather seating surfaces and wood trim. The AT4 gets dark aluminum trim inside to match the exterior, and leather-trimmed seats with contrasting stitching come in special colors.

For tech, the Sierra offers a color head-up display and an upgraded rearview “mirror” that relies on a wide-angle image from a camera in the back. We’ve seen it in certain Cadillac models, where it provides a clear view behind and one that is not compromised by the head restraints. 

2019 GMC Sierra interior showing the new head-up display

What Drives It

Like the Silverado, trucks have updated V8 engines (5.3-liter and 6.2-liter) that use an advanced cylinder deactivation system to help optimize fuel efficiency. A 3.0-liter diesel six-cylinder also joins the lineup for the first time. A 10-speed automatic transmission will be mated to the 6.2-liter V8 and the diesel engines.

We hope the new powertrains and weight savings will make the Sierra more nimble and efficient. CR’s testers got only 16 mpg in the outgoing vehicle, and we complained that the truck felt “a bit sluggish in everyday driving” with the 5.3-liter V8.

Safety and Driver-Assist Systems

Blind-spot warning and automatic emergency braking are standard only on the top-of-the-line Denali trim, and optional on the SLT.

A surround-view camera system is available. In addition, the Sierra offers a trailer-mounted HD camera and available side-view cameras for improved visibility during trailering and hitching. A trailer-specific app walks drivers through the hitching process and troubleshoots any problems with lighting and tire pressure, and drivers can receive alerts through OnStar if a trailer is ever disconnected without their permission.

CR's Take

While the trick tailgate sounds useful, we're skeptical that traditional truck buyers will spring for it—and the same goes for the carbon-fiber bed.

Still, there's a lot of interest in luxury pickups, like the Ford F-150 Limited and Ram 1500 Laramie, which explains why GMC held special debut events for the upscale Denali and AT4 trims. 

2019 GMC Sierra multiposition tailgate