In my experience, where it's 3 lanes each way, the effective 401 speed limits have often been:
Right lane: 105km/h Middle lane: 120km/h Left lane: 130km/h. I don't think that will change with the new signage, maybe 130 and 135 for the left two lanes.
Where it's 2 lanes, the 401 has these effective speed limits:
Right lane: The speed of the truck. Left lane: The speed of the other truck passing the one in the right lane.