Exclusive: Taxi driver's son has 'no doubt' his father killed Sharron Phillips

The son of the man named as the killer of Sharron Phillips said there is "no doubt" his dead father was the murderer.

The man, who doesn’t want to be identified, made the comments during an exclusive interview with 9NEWS.

It comes as police name taxi driver Raymond Peter Mulvihill as the principal offender and said if he were alive today he would be arrested and charged with Phillips’ murder.

Raymond Mulvihill was a taxi driver for Ascot Taxis back in 1986 but died in 2002.

Mulvihill, who would have been 37 in 1986, parked his cab at the residence behind a convenience store on Wacol Station Road. 

The phone box where Phillips’ made two calls to her boyfriend to pick her up that night was located at the front of that store. 

“It's been a long time so there is a bit of relief a bit of sadness, Mulvihill’s son told 9NEWS.

He was 19-years-old when he drove to Wacol to pick up his father - the same night Sharron Phillips' car ran out of petrol.

He remembers meeting his father at his taxi and was asked to get out of his Holden Sedan before hearing the noise of two boots close.

As they drove away together in the Holden Sedan, he said there were noises coming from inside the boot.

"It wasn’t a bang, bang, bang - just a thud," the son said. 

The next day he noticed scratches on his father's face.

Later, when he found ladies shoes and a bag in that car boot, his father panicked and took them away.

He finally confessing all in 2002 while on his deathbed.

"He said it was Sharron Phillips," the son said.

"Then on his death bed said we've got to give back, that Sharron girl, she's buried in the drain."

Police searched that Carole Park drain last year but found nothing.

Police have corroborated his story and believe it stacks up.

Detective Inspector Damien Hansen told 9NEWS police would not stop searching for Phillips’ remains.  

While the case may be solved the seasoned detective said “knowing that Mulvihill is deceased and will not go through court is an empty feeling.”

Phillips' cousin, Morgan Cooper-Phillips, told 9NEWS that the developments have offered closure for the family.

The finger had originally been pointed at Sharron’s father Bob Phillips, but police have now ruled that out.

Detectives will continue to investigate if anyone else was involved in Phillips’ murder.

Investigators now want to speak to anyone who knew Mulvihill.

Detectives also want anyone who lived in Russell Drive, Redbank, during that time, to come forward. 

In particular, they want to speak with a former resident "Jim" who lived across the road. 

Police are also searching for the person who in 1990 bought the pictured brown and white HK Holden Sedan.  The car was later stolen and found burnt out.