GM introduced a new frame and suspension that would boost the Chevy Silverado heavy-duty pickups and GMC Sierra HDs to the top of Class 2 for payload and conventional-hitch towing capacity. Cast independent front suspension components replaced stamped and formed control arms, raising the front-axle weight rating 25 percent to more than 6,000 pounds. Now all cab configurations of four-wheel-drive GM heavies can handle a snow plow.