Marcel Balan, 57, came to a halt on the A19 near Sunderland in March last year having missed his turn off and attempted to reverse.
His dangerous decision resulted in the death of 24-year-old John Robinson, who was travelling behind in his Ford Fusion which collided with the back of the stationary HGV.
The impact of the collision in pitch-black conditions saw the lorry pushed forward eight metres as the victim’s car went underneath it.
Balan, of Cope Street, Barnsley, was subsequently charged following Mr Robinson’s death but denied causing death by dangerous driving.
But on Wednesday a jury found him guilty of the offence after an eight-day trial at Newcastle Crown Court and he is due to be sentenced next month.
Sgt Steve Armstrong, of Northumbria Police, paid tribute to Mr Robinson’s family and said the incident should act as a sobering reminder to all motorists.
“Our thoughts go out to Mr Robinson’s family and friends who have had to endure an incredibly difficult ten months since this tragic incident,” he said.
“Their pain was compounded as Balan opted to take this case to trial, with Mr Robinson’s family forced to re-live the events of that night which saw their son cruelly taken away from them.
“While no ruling can ever take away their anguish, I hope the conviction can give them some kind of justice which allows them to continue with the next stage of their grieving process.
“Balan’s actions that night were irresponsible and incredibly dangerous. He has caused a huge amount of pain to so many people as a result of his behaviour behind the wheel.
“The laws of the road are not optional and they are not negotiable - they’re there to keep people safe and by ignoring them Balan directly put the lives of Mr Robinson and other road users in danger.
“He now must face the consequences of his actions.”
The court was told Balan had made a delivery at Simonside Service Station in South Shields shortly before the collision on the evening of March 12 last year.
He then set off to make another delivery at a national coffee chain in Sunderland and was travelling southbound on the A19 carriageway.
But after travelling past the turn-off for the A1231 Wessington Way, Balan made the decision to stop his lorry in the inside lane of the carriageway.
Seconds later, Mr Robinson’s car collided into the back of the lorry - causing fatal injuries - and he was pronounced dead at the scene.
Upon arrest, Balan claimed he had come to a ‘gradual stop’ on the carriageway because he had ‘heard a noise in his lorry and feared his cargo had come loose’.
This was contradicted by the data from his vehicle’s tachograph and dash-cam footage, and there was no evidence of his load being insecure.
In a statement, Mr Robinson’s family said: “We are very grateful for all the professional, painstaking work that both Northumbria Police and the Crown Prosecution Service (CPS) have carried out to see how this dreadful incident happened.
“No matter what the outcome of this trial, it will not change the fact that we have lost our lovely John and this will affect us for the rest of our lives.”
Balan was remanded in custody and he will appear before Newcastle Crown Court again on February 7 to be sentenced.