A South Australian company has been ordered to pay over $1 million for dozens of dangerous offences.

A New South Wales court has found Mount Gambier-based company Scott’s Transport guilty of an incredible 165 speeding offences, as well as other issues including a speed limiter compliance offence.

The firm faces a total of $1.25 million in fines, part of which were imposed on Manager Peter Anderson and Director of the Scott Group of Companies, Ray Scott.

Ray is the son of the prominent trucking magnate, the late Allan Scott.

The offences allegedly occurred over about two years to March 2012.

In one case, a driver was caught doing 142km/h on the highway, while another was found to be running without a speed limiter.

Executive Director of the South Australian Road Transport Association (SARTA), Steve Shearer says he hopes the court's decision will ring loud, sending a 'major message' to the trucking industry.

He described the easily-deadly speeds some drivers were found doing as “absolutely outrageous”.

“The truck driver in any circumstance shouldn't be speeding and shouldn't be doing anywhere near 140,” Shearer said.

The fines levelled in New South Wales are the highest ever of their kind, and were made possible by strengthened chain of responsibility laws were introduced in 2005.

“The supervisors, the owners, the managers and even the customers at either end, they all have to take all reasonable steps to ensure that trucks aren't speeding, that drivers aren't fatigued, the truck is not overloaded and that its properly maintained,” Shearer said.