Shortly after 12.30pm yesterday, Barwon Highway Patrol officers on the Newell Highway detected a truck travelling at 125kph, in a 100kph zone.
When officers stopped the 33-year-old driver, he allegedly admitted to tampering with the speed limiting device.
Officers issued the driver with a defect notice and will continue their investigations into the history and traffic record of the driver.
Superintendent Stuart Smith, Operations Commander of the NSW Police Force's Traffic and Highway Patrol, said this is gross negligence on the part of the driver and operator of the truck.
"The joint heavy vehicle taskforce continues to identify and prosecute those that deliberately tamper with speed limiting devices for the benefit of road safety for all NSW road users," Supt Smith said.