The new full-size pickup spent more development time in a wind tunnel than any GMC pickup before it to achieve improved airflow, which improves fuel efficiency and interior quietness.
DETROIT- The 2014 GMC Sierra went through more aerodynamic wind testing than any previous pickup for the brand, according to General Motors Co.
Wind testing helps improve airflow, which boosts fuel efficiency and interior quietness.
“We can’t stop air; we can only guide it through the path of least resistance. It’s like electricity, without the shock,” said Diane Bloch, GM aerodynamic performance engineer. “The biggest misconception is that it’s all about single components. But a certain side mirror design doesn’t create a certain amount of drag, its interaction with the rest of the vehicle does.”
To study the way air passes over, under and around the Sierra, engineers used GM’s state-of-the-art aerodynamics lab, a 750-foot-long tunnel through which a 43-foot-diameter fan to generate winds of up to 138 miles per hour.
Aerodynamic advancement, according to GM, is one reason why the 2014 Sierra will be the most fuel-efficient V8 pickup on the market.
GM started production of the 2014 GMC Sierra and Chevy Silverado pickups in Silao, Mexico, earlier this month.
The 2014 GMC Sierra will have a manufacturer’s suggested retail price of $25,085, including a $995 destination fee.
Standard crew cab models are expected to arrive in some dealerships later this month. Double cab and regular cab models should start to arrive later in the summer,
Here’s a look at some of GM’s new features and findings from its extensive wind tunnel testing on the new Sierra:
- A new air dam below the 2014 Sierra’s front bumper successfully reduces drag because it directs air toward the ground and away from the truck’s rough underbody.
- Ducted flow path between the grille and radiator prevents air from swirling inside the truck’s front cavities.
- The Sierra’s tailgate and the center high-mounted stop light are optimized to guide air cleanly around the truck. And new sealing in the cab and bed also help.
- GM found trucks achieve better fuel efficiency with the tailgate up. As air flows over the truck, it falls over the cab and pushes forward on the rear of the truck. With the tailgate down, the benefits of that airflow are diminished.
“Replacing the tailgate with an aftermarket net is worse than having no tailgate at all,” Bloch said.
- What accessories can truck owners add to help aerodynamics? Tonneau covers for the bed help smooth airflow over the truck, and Bloch says soft covers are more beneficial than hard covers because they form to how the air wants to flow. Running boards can also help air flow smoothly down the truck’s sides.