David Leslie, 49, of Balmedie, worked for a feed services firm and was picking up a load from East Coast Viners Grain LLP's site in Drumlithie, Stonehaven, when the incident happened on March 18, 2013.
Aberdeen Sheriff Court heard that Mr Leslie was standing near the base of the grain elevator, which carries the animal feed up and drops it into a bulk transporter, and was ready to pull the lever in the grain bin to release the feed.
The forklift driver picked up the grain bin, which weighed around 600kg and held 1.5 tonnes of feed, and raised the forks to about five and a half feet to allow better visibility as he moved forward. However, the bin started to slide from the forks and Mr Leslie was pinned beneath it when it fell.
He died as a result of crush injuries to his head, neck and chest.
An investigation by the Health and Safety Executive (HSE) revealed East Coast Viners Grain LLP did not have in place a safe system of work for the task and operators were left to carry it out in any way they saw fit. The company had assumed the forklift training they had received from an external provider would cover safe working.
HSE also found that despite previous incidents of grain bins slipping from the forks of the trucks, no mechanism or device to secure them had been installed. There was also poor visibility in the loading area.
Since the incident, the company has stopped using metal grain bins and now uses cloth bags only. It has also updated its risk assessments and work procedures and no longer allows visiting drivers to assist in any lifting operations.
The grain firm was fined £240,000 after pleading guilty to health and safety failures in relation to the tragedy.
The court heard the company had been fined £4,000 in April 2011 over a previous breach in which a mill worker suffered head injuries in a fall.
HSE principal inspector Niall Miller said Mr Leslie's death could have been "easily prevented".
"The issues with unsecured loads on forklift trucks and the dangers of inadequate segregation of vehicles and people are well known in all relevant industries. Around a quarter of all workplace transport incidents involve forklift trucks, with 50 per cent of these happening because someone is hit either by the vehicle or a falling load.
"It was entirely foreseeable that there was a risk of death or serious injury if the grain bin fell from the forklift truck, particularly as the company was aware of previous incidents of loads falling."