The structure, between Castletown and Pallion, weighs the equivalent of 125 double decker buses and will be supported by a 379ft (115m) pylon.
David Abdy, project director for Sunderland City Council, said the Â£117m bridge was essential for the city.
The bridge and its approach roads are due to be open by 2018.
It is the first bridge to be built in the city for more than 40 years.
The bridge's pylon is twice as high as the Millennium Bridge in Gateshead and taller than Big Ben's clock tower.
It will have two lanes of traffic in each direction, plus dedicated cycle paths and footpaths along its full length.
The 330ft (100m) centrepiece of Sunderland's new River Wear road bridge has begun its two-day journey being lifted in to place.