The housemate of murder victim Andrew Carville has been identified by ACT police as a suspect, along with one of her associates.

Charges have not been laid but police hope a motorist who was forced to swerve around cars parked on a rural road in November could help solve the case.

Mr Carville, aged in his 50s, was found dead on Defence land at Majura, north of the airport, on November 19.

He had been missing for three weeks.

On Wednesday police confirmed that Mr Carville's housemate, along with the housemate's associate were suspects.

The associate owned a Toyota LandCruiser linked to Mr Carville's death.

"The Toyota LandCruiser is related to [Mr Carville's] housemate [who] was moving out of the residence on the night of the 4th of November," Detective Sergeant Donna Parsons said.

"We are following up all their movements to determine their involvement in this murder."

Police are calling for witnesses travelling on Kuringa Drive in Fraser on Wednesday November 4 between 10:45pm and 11:15pm.

In particular, anyone who may have seen a 2015 orange-coloured Holden Colorado ute and a 1986 cream-coloured Toyota LandCruiser parked the road.

"There was a vehicle travelling along Kuringa Drive that needed to swerve around these two vehicles in order to avoid a collision," he said.

"We are appealing for the driver of that vehicle."