Police from the Cold Case Homicide squad are chasing a fresh lead into the murder of Josh Warneke on the outskirts of Broome more than seven years ago.
They want to find the owner of a white Toyota '79 series Land Cruiser tray top ute that was seen not far from where Mr Warneke's body was found in February 2010.
Police say the vehicle had a "Bundy" novelty number plate and car flag poles on either side of the frame behind the cab.
Acting Detective Superintendent Pete Branchi from the Special Crime Division said the Land Cruiser drove along Short Street into Old Broome Road around the time of the 21-year-olds' death in the early hours of February 26.
"Despite all the publicity about this case since 2010, the driver of the Land Cruiser has never come forward, " he said.
"We are appealing for public assistance to identify the vehicle, its driver and any other occupants."
Mr Warneke's body was found on the outskirts of Broome after he spent a night out with friends and decided to walk home to Roebuck Estate.
A taxi driver found his body on the side of the road at 2:54am.
WA Police announced in April this year they would begin a new investigation after the man jailed for killing Mr Warneke, Gene Gibson, walked free in April when the WA Court of Appeal overturned his conviction.
Superintendent Branchi said police believed the occupant or occupants of the Land Cruiser saw Mr Warneke on Old Broome Road around the time of his death.
"So it is very important we speak to the driver and any passengers of that vehicle, or anyone who has information about that vehicle and its occupants," he said.
"Their information, however insignificant it may seem to them, may help bring Josh's killer, or killers, to justice."
In a statement provided to the ABC, Mr Warneke's mother Ingrid Bishop said she was encouraged to see new leads being investigated, and hoped it would prompt somebody to come forward.
"To have a rethink about any comments or information that they have heard of over the past years," she said.
"It's so important that people pass on any information that they have heard as it could be the key to finding Josh's murderer.
"It's disappointing that the occupants of the vehicle have not come forward before, [but] perhaps they will now."
The State Government is offering a $250,000 reward for information about the murder.
Police say they will also recommend protection from prosecution, or a pardon in some circumstances, for anyone not directly involved in his death.
