It follows pressure from hauliers who say a 10mph increase on the current national speed limit of 40mph for trucks would cut fuel bills, reduce carbon emissions and improve safety as car drivers would feel less inclined to overtake on dangerous stretches of road.
A consultation on raising the limit for HGVs weighing more than 7.5 tonnes was launched yesterday by the Department for Transport. That will cover roads in England and Wales.
However, officials at the Government agency Transport Scotland are understood to be considering similar proposals to apply to trunk roads in Scotland.
Powers over speed limits were devolved to Holyrood from Westminster earlier this year.
The issue is of particular importance to Scotland which, because of its topography, has a higher proportion of long single-carriageway roads carrying large volumes of traffic than other areas of the UK, leading to a higher accident rate.
Phil Flanders, director of the Road Haulage Association for Scotland, said he had held productive meetings with officials this week over how the speed limit could be changed.
He said research by Transport Scotland showed a new, strictly enforced 50mph limit for trucks along with the existing 60mph limit for cars would cut accidents by up to 18%, and queues would be cut from 18 vehicles to six.
Mr Flanders said: "Our argument has long been that the 20mph differential between lorries and cars is too high.
"On the A9 for example, everybody complains lorries go too slow and are holding cars up.
"If lorries were allowed to go a bit faster, there wouldn't be as many on the road and it would help boost the economy."
Neil Greig, director of policy at the Institute of Advanced Motorists, has also backed the plans.
He said: "Drivers are often ignorant of the different speed limits for HGVs and platooning behind HGVs often leads to drivers getting frustrated and making risky overtakes, particularly on roads such as the A9."
However, the increased limit has been opposed by sustainable transport lobby group Sustrans, which claimed it would lead to increased risks for cyclists.
Jason Torrance, the charity's policy director, said: "This decision will only make our roads more dangerous for those at the greatest risk."
A Transport Scotland spokesman said: "Road safety is a top priority for Transport Scotland. The Scottish Government now has powers to set national speed limits, including vehicle speed limits, for the nation's roads."