James Brown, 57, struck Samuel Smith, 50, with the Toyota vehicle in Broomknowes Road, Glasgow, before assaulting him on July 6, 2013.
Brown, a prisoner of HMP Barlinnie, was convicted of assaulting Mr Smith to his severe injury following a week- long trial at the High Court in Edinburgh last December.
The court had heard Mr Smith, 50, say Brown drove the vehicle which hit him before he and two other unknown men got out and struck him on the back with a "bat or a cosh".
Mr Smith thought he had been picked on because his attacker felt he had been spreading rumours about his alleged relationships with other women.
Yesterday, Lord Stewart told Brown a custodial sentence was the only option available to him.
He added: "This is a very serious offence."
Sentence had been deferred in order for the court to obtain reports about his character.
The judge rejected pleas from Brown's legal team that he should be spared jail because of his age.
He also banned Brown from driving for 10 years.