High-Strength Steel Replacing Roll-Formed Steel In New Cabs And Frames
How tough are heavy-duty trucks? GM put their 2015 Silverado HD to a twist-test against a comparable Ford Super Duty to show the benefits of increasing the use of high-strength steel in frame rails and cabs.
AMCI found that during the GM test, the Silverado HD’s frame allowed 0.26 inches of twist, while the F-250 Super Duty allowed 0.94 inches of twist, 262 percent more than the Silverado. (GM Photo)AMCI Testing, a third-party research firm hired by Chevrolet, recently subjected the 2015 Silverado 2500HD and a Ford F-250 Super Duty to a rigorous frame twist test, in which the truck was driven onto two staggered ramps, where the wheels on one side of the truck hit the ramp before the other, placing a large amount of torque on the frame.
Measurements were then taken for the distance of displacement of the cab body and the bed, determining the amount of twist to which the frame is subjected.
The twist was so great on the Ford that when under stress, the tailgate could not able to be lowered, while the Silverado’s available EZ-Lift and Lower Tailgate operated normally. You can see the test here.
“The use of high-strength steel in the Silverado HD is what allows the Silverado to handle even the toughest of jobs,” said Jeff Luke, General Motors’ executive chief engineer for full-size trucks. “Paired with a fully boxed frame, high-strength steel is what makes the Silverado come from the family of the most dependable, longest-lasting full-size pickups on the road.”
Roll-formed steel in the Silverado HD vs. the stamped steel bed of most competitors involves using a higher-grade steel that’s stronger, lighter and more durable. The fully boxed frame provides a rigid foundation.
The Silverado’s body is also constructed using similar high-strength steel. Approximately 67 percent of the cab is constructed with high-strength and ultra-high-strength steels. They’re used in the A-pillars, B-pillars, rockers and roof rails, as well strategic sections on the interior structure.
Ultra-high-strength steel is used in areas of the rocker panels and underbody to help improve crash performance.
GM says the Silverado HD uses more high-strength and ultra-high-strength steel than any competitor’s [current] full-size pickup truck, according to market research firm Ducker Worldwide.
Ford’s 2015 F-150, which goes on sale later this year, has more than 78-percent high-strength and ultra-high-stregth steel in the fully-boxed frame supporting the aluminum body and bed. The 2016 Super Duty will feature similar design according to Ford sources.
