The Opposition last week released a secret map produced in May by the Department of Transport showing proposed B-triple truck routes in Victoria.

Major roadways proposed for use include EastLink tollway to Frankston and Western Port Highway to Hastings.

B-triples are a B-double with an extra trailer at the front. They weigh up to 100 tonnes. B-triples up to 53 metres long are allowed to operate in some states and in the Northern Territory.

The Opposition's spokesman on public transport and roads Terry Mulder said the Government was determined to "force these longer, heavier trucks onto Victorian roads such as EastLink, roads in Frankston and Scoresby and on the Western Port Highway to Hastings without any community consultation".

Mr Mulder said the map showed B-triples were set to travel along the whole of EastLink from Donvale to Seaford, through Frankston on the Frankston Freeway and on part of the Moorooduc Highway to Frankston South.

Trucks would use the Western Port Highway from Hastings to its junction with the South Gippsland Highway, the Monash Freeway and most of CityLink.

"The map excludes local roads that will be used by B-triples when they leave freeways, highways, tollways or arterial roads. They cannot simply stop in Frankston South ... after using EastLink or the Frankston Freeway."

Mr Mulder accused the Government of pushing for B-triple road trains.

"This is John Brumby's fall-back plan because of his failure to transfer freight to rail as Labor promised."

He said Roads Minister Tim Pallas last December promised full consultation with local communities and councils over B-triples on Victorian roads.

The push to get bigger trucks onto Australian roads started in early 2006 when the Council of Australian Governments (COAG) agreed to identify a suitable road network for B-triples to improve the safety and efficiency of freight transport.

B-triples are widely used in rural and remote areas for carrying livestock and bulk commodities. A small number of B-triples have been operating between Ford's Broadmeadows and Geelong plants for about 10 years.

COAG has stated extension of the B-triple network may be conditional on planning and funding to improve the road infrastructure, including road widening, town bypasses, overtaking opportunities, intersection improvements, upgraded rest areas and trailer breakup areas.

Mr Pallas said using B-triples would mean fewer trucks on the road.

VicRoads would consult with local councils before introducing B-triple routes, he said.