Traffic chaos in North Melbourne has been cleared after a truck earlier brought down tram lines during the peak-hour rush, closing roads and causing major delays for drivers and commuters.

All lanes were reopened just before 3pm on Monday, with VicRoads also confirming the inbound on-ramp to Citylink had also been reopened.

Traffic in North Melbourne was earlier gridlocked with a five-kilometre traffic jam from Carlton to Flemington after the truck tore down the overhead lines on Racecourse Road about 7am.

All outbound lanes on Racecourse Road in North Melbourne and the CityLink inbound on-ramp were closed for several hours while route 57 trams were diverted.