CRASH scene investigators believe the b-double involved in Sunday's horrific Urunga crash ran off the road to avoid a collision with a utility. 

The south-bound truck and ute, which was headed north, collided on a 60km/h stretch of the Pacific Highway in the heart of the town on Sunday about 5am.  

Police say its believed the driver of the b-double swerved to avoid an impact with the ute as it travelled on the wrong side of the road.

The 2002-model Kenworth prime mover and trailers carrying bananas then careered off the roadway and crashed into a family holiday house, killing 11-year-old Max McGregor who was asleep in a bedroom at the time.

His parents, brother and two neighbours escaped with minor injuries and were taken to Coffs Harbour Hospital for treatment. The family from Penrith had been holidaying on the coast.

The driver of the ute, Nambucca Heads father of two David Levett, 38, also died at the scene. 

The truck driver, a 51-year-old Queensland man and a 31-year-old passanger, who suffered chest injuries are expected to be released from the Coffs Harbour Hospital unit later today.

Senior Constable Andrew Nelson, from the Mid North Coast Crash Investigation Unit, said it did not appear the ute was trying to overtake.

"As to why he's on the wrong side of the road, I don't know," Senior Constable Nelson said. 

"Early inquiries suggest that there's, at this stage, no other vehicle involved.

"There's no allegations of him trying to overtake a vehicle."

Senior Constable Nelson said that, while police were awaiting the results of tests on the drivers, there was no allegation that drugs or alcohol were involved.

Officers attached to the Mid North Coast Crash Investigation Unit are continuing their investigations into the circumstances surrounding the incident but do not believe speed was a factor.

The Urunga accident was this morning followed by another double fatal on the Pacific Highway, south of Port Macquarie near Kew.

Police said a man and woman in their 20s or 30s died when their Toyota Rav4 veered off the road and crashed into a tree they were later found deceased in the vehicle.