The collision took place between two HGVs and a car in the early hours of 13 January.
The M6 Southbound was closed between junctions 33 and 32 for around six hours to allow recovery and investigation work.
Force Incident Manager for Lancashire Police Grant Smith said: "Driving conditions are particularly treacherous this morning - it's like driving on glass. Please be very careful and allow extra time to complete your journeys."
It is not thought that anybody was injured as a result of the accident.