A VICTORIAN company is at the centre of police investigations into a runaway truck on South Australia's South Eastern Freeway.
The incident comes only a short time since the deaths of two motorists earlier this month when a runaway truck collided with three vehicles at the intersection of the South Eastern Freeway, Cross Rd and Glen Osmond Rd.
Since that crash a 90kmh speed limit was applied for all light vehicles Freeway between the Stirling interchange and tollgate and all trucks and buses were restricted to 60kmh from the Crafers Interchange to the bottom of the freeway.
Superintendent Bob Fauser, the officer in charge of the Traffic Support Branch, said SA Police have been liaising with authorities in Victoria along with the National Heavy Vehicle Regulator as the investigation continues.
The driver, a 32-year-old from Croydon South, has been reported for driving without due care and regulatory offences.
Superintendent Fauser said the driver told officers that he did not use the arrester bed below the tunnels as he believed he was going to bring the truck under control.
"That turned out to not be the case," he said.
"This incident was nearly disastrous. If not for the actions of the officers involved, this could have been a terrible tragedy.
"The officers were on the freeway as part of our enforcement of the new regulations, but it is vital that the trucking industry plays its part in keeping all road users safe.
"This vehicle had malfunctioning brakes on the prime mover and no functioning brakes on the rear trailers - a completely unacceptable situation on our roads.
"We will continue to pursue all legal options with regard to this company, and make no apologies for the focus we will continue to place on enforcing standards in the trucking industry."
Police have released audio of the emergency calls made by police who found the truck hurtling down the highway.
The action taken by the two police officers to narrowly avoid a disaster has been described as "extraordinary".
The Victorian truck driver involved in the incident has been reported for driving without due care and regulatory offences.
About 11.45am a police patrol from the Eastern Adelaide traffic section was driving on the up-track of the freeway on a routine patrol when they noticed a truck coming out of the tunnel with smoke coming from its wheels.
Realising the vehicle was in trouble, the officers made a u-turn, activated their lights and sirens and contacted traffic management to arrange control of the traffic lights.
The lights at the Glen Osmond, Portrush, Cross roads intersection with the freeway were turned green to allow the truck, under escort by the police vehicle, to travel through the intersection.
The police patrol continued to escort the truck until it was able to safely stop near Glen Osmond Rd and Wattle St.
Following an inspection of the vehicle, police will allege the prime mover had oil in its air tanks, which meant the brakes were malfunctioning, and that neither trailer had working brakes. It will also be alleged the second trailer had cracks in the suspension and axel components.
Superintendent Bob Fauser, the officer in charge of the Traffic Support Branch, said the officers involved had done an "extraordinary thing" today with their actions potentially preventing a disastrous accident.
No one was injured in the incident.
New rules for the freeway say that trucks and buses must use a a gear that is low enough to limit the speed of the truck or bus without the need to use the primary brake.