A badly injured woman survived three freezing nights thanks to her beloved dog keeping her warm after their vehicle crashed off the road and plunged 45m down a steep bank.

The 63-year-old was only rescued after hikers heard her dog's barks and noticed the mangled wreck of her car wedged in a streambed at the bottom of a gully.

A friend is amazed the woman survived, crediting her strong will and the devotion of her canine pet.

Kerry Jordan set out from Masterton to travel to Palmerston North last Thursday. But her car left the road on the eastern side of the Pahiatua Track, and after tumbling 45m down the steep gully she found herself trapped in the wreck, with a broken ankle and collarbone, and a crushed chest and sternum.

Though badly injured, it is understood she dragged herself out the driver's side window and sheltered under a bush with only her faithful 5-year-old Border Collie cross Pat for company.

Friend Fiona Northe said she waved Jordan off from Masterton at 5.30am on Thursday.

Jordan had promised to text when she arrived in Palmerston North. Northe wasn't too worried when she hadn't heard from her friend on Thursday but began to worry when there was still no communication on Friday.

Calls and texts to Jordan's mobile phone over the weekend went unanswered and by Monday Northe was very worried.

Later that day police advised Northe that Jordan had been in a crash and was now in intensive care at Palmerston North Hospital.

Police, Fire and Emergency personnel and a Palmerston North Rescue Helicopter crew attended the scene on Sunday afternoon after being alerted to Jordan's plight.

A rescue chopper spokesperson said the dog ran away when the helicopter arrived, but they knew Pat was around because Jordan kept asking for her beloved pet.

Northe believed Pat sheltered Jordan from the time of the crash on Thursday morning until sometime on Sunday when he got the attention of two passing hikers.

Originally, they thought the car had been abandoned but took a closer look when they saw a dog barking beside the wreck.

The hikers alerted emergency services who scrambled to the scene. Jordan was then airlifted to Palmerston North hospital where she remained yesterday in intensive care.

Speaking from Jordan's bedside in hospital yesterday, Northe said the police had told her the dog appeared to have kept her friend warm during the three-day ordeal.

Northe said Jordan was devoted to the dog and referred to Pat as "her son".

"It's amazing that she lived, and you hope that pneumonia doesn't settle in, but she is pretty strong-willed."

The dog is currently in a Palmerston North pound and Northe planned to bring him home on Monday.

The MetService said there would have been rain in the Ballance Rd area on Thursday, with a chilly low of 7C on Saturday night.