Emergency crews worked for three hours to extract a truck from an embankment after it crashed through a wire safety barrier on Sunday night.
The prime mover and a semi-trailer ran off the road on the Princes Highway east of Camperdown.
The incident happened about 7pm Sunday and traffic was diverted down Stoneyford Road.
"There was no-one trapped and no fire as a result," a CFA spokesman said.
"The semi-trailer ran off the road and through the barriers and blocked the whole highway, causing significant traffic problems.
"Heavy haulage was required for a single trailer and two crews from Pomborneit and Weerite attended. It took three hours to remove."
Police believe wet conditions and the road surface may have contributed to the accident.
"There's an investigation in relation to fatigue and surrounding offences," a Camperdown member said.
No paramedics were required on scene, an Ambulance Victoria spokeswoman said.
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