In an unusual coincidence two koalas have survived being hit by cars at high speed near Adelaide by wedging themselves in the front of cars.

In the Adelaide Hills on Thursday, a driver reported hitting a koala which then lodged into the car's front-end.

The koala "lived to tell the tale", and the incredible story prompted a southern suburbs woman to recall a similar situation.

For Rachel Allgood, an early morning drive home from work three weeks ago turned into a trip she would never forget after she collided with the koala.

Ms Allgood was travelling along Lonsdale Road, Lonsdale, and had just shifted from the 100 kilometres-per-hour zone to the 80 zone when she spotted the animal in the middle of the road.

"I had cars to the side of me and cars behind me, so I could not swerve or brake," she said.

"I unfortunately had to hit it and did not think the koala would survive."

She continued on her drive home and parked in her drive, only to hear unusual sounds coming from the front of her car.

The koala was wedged in under the bumper bar.

Scratches and damage to Ms Allgood's car after the koala was safely removed. She later discovered her radiator had been damaged as the koala tried to free itself. ( Supplied: Rachel Allgood )

The koala had tumbled head-first into her vehicle's lower air intake, and had clung to the car for the ride home.

"His head was totally lodged into my grille," Ms Allgood said.

"I was stunned, I did not know if it was okay and was a bit too scared to go near it."

She ran to a neighbour's house for help and a man used kitchen gloves to pull the koala from the grille.

"He was fine, and he started running around my front yard for a couple of minutes," Ms Allgood said.

After hearing Ms Allgood's dog bark, the koala took off down her driveway, jumped a neighbour's fence and scaled a tree.

Ms Allgood called a koala rescue organisation and within two hours the animal was in their care.

After a veterinary check, it was confirmed the koala came out unscathed.

The koala's revenge

Several days after the incident, Ms Allgood was driving her car when the dashboard started to light up.

"About five days later I was driving home from work and the temperature gauge started to climb quite quickly," she said.

"I had a message coming up saying the engine was overheating, so I pulled over quickly."

Turned out Ms Allgood's unexpected passenger had managed to do considerable damage to her vehicle.

"There was radiator fluid going everywhere," she said.

With her car now repaired and the koala safely relocated, Ms Allgood said she still felt a little nervous driving along the same stretch of road each day.

"I definitely think about it every time drive along that road now," she said.