She was identified by the Will County Coroner as 28-year-old Perla Andrade-Garcia.
She was driving northbound on I-55 around 3:23 a.m. when she reportedly ran out of gas and got out of the car with a passenger.
Illinois State Police reported that a semi truck hit two pedestrians on the shoulder of I-55 before fleeing.
Andrade-Garcia was pronounced dead on scene. The passenger was transported to an area hospital with serious injuries.
There were reports of a seven-mile backup all the way back to Route 126 as police investigated.
Andrade-Garcia's mother said on a GoFundMe page for her daughter's funeral expenses that she leaves behind two children.
Police were still searching for the driver who hit the victims.