The Friday night crash killed 17-year-old Choice Taylor, a senior at Maine West high school.
Police said Sunday that the vehicle involved was a red or maroon semi-tractor. It was not pulling a trailer. Authorities say they think Taylor somehow became entangled in the rear wheels of the truck as it traveled down Algonquin Road.
Witnesses say the driver did pull over and looked for damage to the truck, but the driver may have continued on, not realizing anyone was hurt.