New Labour Party transport policies, which include plans to ban trucks from around 8 per cent of New Zealand's motorway network, have been met with a mix of praise and scepticism.
Truck drivers said preventing them from using the outside lane on three- and four-lane highways would be unworkable and unlikely to reduce congestion.
The Automobile Association (AA) also questioned the policy, saying its members had never cited trucks as a cause of congestion.
But the AA strongly backed other Labour measures such as scrapping registration fees of $35 for light trailers and caravans and reducing charges for motorhome owners.
Labour leader David Cunliffe said "Kiwis are sweating the small stuff too much" and Labour's changes would reduce frustrations during public holiday periods.
New Zealand Transport Agency records showed the total length of three- or four-lane highways in New Zealand was 840km, out of a total of nearly 11,000km of state highway.
More than a third of these wider motorways were in the Auckland and Waikato regions, where Labour's deputy leader, David Parker, said the policy would be most popular.
"You ask the 1.5 million people in Auckland and they will say it annoys them that at times the fast lane is blocked by trucks that are only meant to be doing 90km/h."
New Zealand Trucking Association head David Boyce said all large trucks already kept to the left lane of highways unless they were passing. He said the policy would be unworkable because trucks often had to use outside lanes, such as when they exited multi-lane highways on the right-hand side.
AA spokesman Mike Noon said the organisation had long lobbied for fairer and simpler registrations and road user charge fees and was encouraged Labour was promising change in this area.
Labour's policy documents said annual registration for caravans and light trailers was "a money grab", and road-user charges for motorhomes did not reflect the vehicles' impact on roads.
The changes would reduce the revenue stream for transport projects by $19-$22 million - less than 1 per cent of the 2012-2015 pool of funding.
Transport Minister Gerry Brownlee said the policies would undermine $12 billion in transport projects, such as the Roads of National Significance.
• Ban trucks from fast lane on three- and four-lane highways.
• Remove annual registration fee for light trailers and caravans.
• Change road-user charges for motorhomes and campervan owners.