They would be instantly billed by automatic vehicle identification systems such as those used to monitor cars on toll roads.
But motorists who drove in non-peak periods and had environmentally friendly cars would pay less for the right to have a vehicle.
And scrapping the present one-charge-for-all system would give low-income earners a chance to cut motoring costs by changing their driving habits.
The proposal is contained in a Budget submission to the Government by the Australian Automobile Association, representing the nation's eight driver service organisations, including the NRMA.
It matches a push in Treasury for the introduction of more user-pays changes, rather than a flat rate for all, and has been endorsed by a government advisory group, the National Transport Commission.
The proposed system has been likened to mobile phone charges. The mobile owner pays one fee to enter the system but all other costs depend on when, to where, how often and for how long calls are made.
The new tax on drivers would include an "access charge" and a "user charge". This tax structure would replace existing charges motorists pay - federal fuel excise, GST on petrol, state registration charges, stamp duty on registration and road tolls.
In 2007-08, excise on petrol will raise $14.42 billion but just $3.41 billion will be spent on roads.

The amount of the user charge would depend on the size of the vehicle and the wear it causes roads, an environmental charge related to engine capacity, a levy to cover the costs of crashes and the congestion charge.
By Malcolm Farr - news.com.au
I commented.
http://www.news.com.au/comments/0,23600 ... -2,00.html
Instead of working on easing congestion using the money available, we'll just get slugged with another tax/levy and nothing will actually be done about it.