Nora Naughton The Detroit News Published 11:50 AM EST Feb 5, 2019 Flint — Chevrolet launched its redesigned 2020 Heavy Duty pickups Tuesday at its truck assembly plant here, the third all-new Silverado in 18 months. The new truck, built at the renovated Flint Assembly Plant, will require 1,000 more workers at the plant, GM President Mark Reuss said ahead of the launch. The General Motors Co. brand gave a sneak peek of the truck in December, debuting a new exterior design that differs from the light-duty Silverado that debuted at the Detroit auto show last year. Powered by an all-new gas-powered V-8 engine paired with the 10-speed Allison transmission that debuted on the new heavy-duty GMC Sierra last month, the new Heavy Duty breaks away from the Camaro-inspired grille design on the 1500 with a bolder fascia and bigger headlights. Chevy said in December that the Heavy Duty trucks only share a roof with the light-duty 1500. Every diesel-powered Chevy dually will now tow more than 30,000 pounds. And the gas-powered 2500 HD’s max towing is 17,400 pounds, an 18 percent increase from the current model. The 6.6-liter V-8 Duramax turbo-diesel engine will develop 445 horsepower and 910 pounds-feet of torque, falling short of the…