Adriana Betty Tennant has been found guilty of manslaughter for striking Nathan Freer with her car in Quorn.
Tennant's verdict was handed down in the Supreme Court in Adelaide on Friday morning and she was acquitted of a charge of murder.
Tennant, 49, had pleaded guilty to manslaughter at the start of the trial but this was not accepted by prosecutors.
Justice Trish Kelly told the court the events unfolded so rapidly that she was not convinced that the accused formed any specific intention at all other than to knock the deceased down.
"However, I am in no doubt that any reasonable person, in the same position as the accused, would have realised that by steering the vehicle directly at, and into, the deceased was exposing him to an appreciable risk of serious injury," she said.
"Therefore, I am satisfied beyond reasonable doubt as to each of the elements of manslaughter by an unlawful and dangerous act."
Tennant hit Mr Freer on Park Terrace with a Mitsubishi Triton on November 24, 2017. Previously, in the Supreme Court in Port Augusta, the court heard the incident followed a falling out between the families over a request to borrow a trailer.
In an usual twist, the footage of the incident was captured on Tennant's dashcam and it recorded the fatal events that unfolded on that day.
Tennant was remanded in custody to face court for a sentencing hearing in September.