Police said the 20-year-old woman was travelling towards Orange on the Mitchell Highway five kilometres west of Bathurst when she lost control of her car and crossed to the wrong side of the road just before 4pm.

Her car collided with a tip truck which was carrying earth moving equipment. The truck was heading east towards Bathurst.

The impact of the collision ripped the engine from the Hyundai and it, along with other debris from the crash, was strewn across the highway.

The collision closed the Mitchell Highway in both directions for more than two hours with an emergency retrieval helicopter landing at the scene.

Paramedics treating the female driver before she was transported to Orange Base Hospital with internal injuries. The driver of the truck was uninjured.

The crash caused havoc on the already congested highway as hundreds of race fans made their way home following the Bathurst 1000.

Traffic was diverted from the Bradwardine Road roundabout through Dunkeld and back onto the Mitchell Highway until the road reopened late on Monday evening.

Police are continuing their investigations into the crash and have already identified and spoken to witnesses.

However, officers are keen to speak to anyone else who may have witnessed the crash and has not yet spoken to police.