THE A4136 at Longhope was engulfed in smoke after a 26-tonne lorry developed a fault.
The lorry, photographed by Jenny George, was travelling up the hill towards Little London when it began trailing plumes of smoke behind it.
It is thought the turbocharger on the vehicle, which is owned by a Lydney firm, failed and leaked oil into the exhaust.
The fire service were called to the scene at 9.07am on Tuesday but it was classified as a false alarm with good intent as the lorry had not caught fire.
The vehicle was recovered by Richard Read Transport and the road was back to normal by 11.20am.