The Highway 427 ramps are both reopened after a tractor-trailer rolled, hit a guard rail and crashed into a pick up truck on Friday.
No one was injured in the two-vehicle crash, which also caused a fuel spill.
Sgt. Kerry Schmidt, spokesperson for the Highway Safety Division of Ontario Provincial Police, said the Highway 427 southbound ramp to Highway 401 westbound was reopened after 4 p.m. The northbound ramp opened about an hour later, according to police.
The tractor-trailer, which was carrying steel coils, rolled across all lanes.
"Cleanup is ongoing right now," Schmidt said.
Police said they believe the tractor-trailer was southbound on the Highway 427 ramp to Highway 401 westbound when it hit a concrete guard rail, rode the rail "for some time" then rolled.
Police said it may have been travelling too fast for the ramp. It struck a pickup truck after it rolled.
The crash, which police said created a "visual distraction" on the highway, caused traffic to back up on Highway 427. There are also delays on Highway 401 westbound express lanes in the area, Schmidt said.