The site has now been cleared following a crash near Woodford on Friday morning.
The accident, between a truck and car, occurred on the Great Western Highway about 9.10am.
The incident happened near Hepburn Road, between Woodford and Linden.
Westbound traffic remains affected, but the congestion is starting to ease.
Motorists should still allow extra travel time in the area.
There are delays on the Great Western Highway following an accident on Friday morning.
The truck and car accident occurred near Hepburn Road, between Woodford and Linden, about 9.10am.
More than an hour later, one westbound lane remains closed to traffic.
According to Live Traffic NSW, there are “moderate” traffic conditions in the area.
Emergency services crews are at the scene.
Motorists should allow extra travel time and exercise caution on the highway.