Truck jackknife on M5 motorway causes major traffic chaos for peak hour commuters in Sydney’s south-west

A truck accident has caused significant disruptions on major roads in Sydney's south-west this morning, throwing the peak hour commute into chaos.

The B-double truck was travelling on the M5 towards the city in the early hours of Wednesday when it jackknifed, causing three of four city bound lanes to shut. 

Motorist heading to the city from Raby northbound through Prestons have been warned to expect significant delays with traffic stretching up to 11 kilometres along the Hume Motorway.

The jackknifing occurred at the end of the M7 off-ramp causing the truck's fuel tank to rupture and oil to spill on the road.

New South Wales Fire and Rescue crews attended the scene to clean the spillage while a tow truck was called to the move the B-double. 

The M7 on-ramp to the M5 has since reopened but one of four citybound lanes remain closed.

Motorists have been advised to allow extra time as traffic is still banked up to Raby Rd.