GMC is preparing its new Hummer EV for the start of production later this year, and has released footage of the cold weather testing program that the vehicle has been through.
Winter testing was undertaken in Michigan’s Upper Peninsula, where the development team put the truck through its paces in sub-zero temperatures on various surfaces, including snow, ice, steep and split-mu grades.
Key tests include refining the all-wheel drive torque distribution with the traction control system, as well as calibrating and testing the electronic stability control system.
The Hummer EV will be the first GMC vehicle in production with the company’s latest Ultium battery architecture. According to GMC, the batteries are unique because of their large-format, pouch-style cells, which can be stacked vertically or horizontally inside the battery pack. In the Hummer, two layers of vertical cell modules are used to produce a combined 24-module pack offering a GM-estimated range of more than 350 miles. The pack’s low mounting position in the chassis, made possible by the cell architecture, also contributes to a low center of gravity, which should improve vehicle stability both on and off road, while also allowing for short front and rear overhangs.
The truck’s three electric drive motors yield a combined GM-estimated 1,000bhp, and when multiplied through the front and rear drive unit gear ratios, provide an estimated 11,500 lb-ft of torque at the wheels. The single-motor front drive unit will have a 13.3:1 fixed-gear ratio and an electronic lockable differential, capable of delivering up to 100% of the motor torque to one wheel, in case traction is lost on the opposite wheel. All four wheels can be fully synchronized for true electric all-wheel drive propulsion.
Two rear motors, contained in a single drive unit, independently power the rear wheels through a fixed gear ratio of 10.5:1, with the capability of varying torque output to each wheel. Motor output can also be synchronized to simulate a locking differential.
