The incident occurred around 4.30am on the westbound off-ramp of the M2 Motorway at Pennant Hills Road in Pennant Hills.
The driver, a man – believed to be aged in his late 50’s – died at the scene and is yet to be formally identified.
The westbound off-ramp is now closed and motorists are advised to exit the motorway at Beecroft Road or Windsor Road instead.
Drivers can no longer use the westbound Pennant Hills Road off-ramp to get to the Northconnex Tunnel to travel north.
The M2 remains open however motorists are advised to allow extra time and exercise caution.
For the latest traffic information, visit www.livetraffic.com, download the Live Traffic NSW app or call 132 701.