CBC's Linda Ward reported from the scene that a Ford Explorer SUV rear-ended a slow-moving or stopped Nissan Altima, causing major damage to the car and killing its driver.
The SUV rolled over but the driver suffered only minor injuries.
The eastbound collector lanes are closed.
Police say drivers can stay in the express lanes and transfer to the collectors after Dixie to access ramps to Renforth Drive and Hwy. 427.
OPP Sgt. Kerry Schmidt said the crash happened just before 3 a.m.
He said it wasn't clear if the car, which was partly on the right shoulder, had mechanical problems. Police will also investigate the speed of the SUV, Ward said.