Queensland Opposition Leader Deb Frecklington has promised to expand the Bruce Highway if the LNP wins government at next month's election.
The highway would be upgraded from Far North Queensland down to Gympie at the northern end of the Sunshine Coast, a project expected to take 15 years to complete.
Ms Frecklington said the work would cost an estimated $33 billion and bring 100,000 jobs to the state.
"We will make Queensland's most important road, Queensland's best road, we'll make the Bruce safer, stronger and better for business," Ms Frecklington said.
She said the highway was currently unsafe.
"I'm quite sure there will be many people who look forward to a safer Bruce — particularly those families of the [people who] lose their lives each and every year," she said.
"We must do something to invest in Queensland's future."
Paul Turner from the RACQ welcomed the plan to upgrade the Bruce Highway, which he said "still has some sections rated two stars out of five".
"[It] is hardly a world-class road in a world-class country and state like Queensland," he told ABC Radio Brisbane.
But Mr Turner said the funding should be focused on areas where upgrades would do the most good, rather than simply marginal seats.
He said road safety, capacity, logistics and flood mitigation all needed to be addressed.
"Proper duplication with the right funding would actually fix most of those areas," he said.
Ms Frecklington said the upgrade would target crash zones and areas at most risk of flooding.
She said $50 million would be invested in a "detailed planning study" of the upgrade.
In July, the LNP committed to spending $1 billion on infrastructure spending, including $245 million to build a new bridge over the Brisbane River on the Centenary Highway at Jindalee, which is in the marginal electorate of Maiwar.
A 'fantasy' with no federal funding
Queensland Transport Minister Mark Bailey said the LNP's election promise was not practical or achievable.
"This announcement is just another unfunded Deb Frecklington fantasy with no Federal Government funding attached to it," Mr Bailey said.
"All she's got is a $50 million study for consultants — not a cracker in there for Bruce Highway motorists.
"New South Wales has been duplicating their highway — 650 kilometres, less than half of what Deb Frecklington is talking about today — it's taken them 25 years and they're still going."
