Roads Minister Michael Knight paid the last $1 toll at the Waterfall toll booths.

The move was promoted as the fulfillment of and election promise but, in reality, the government-funded road was close to being paid off from tolls collected from motorists over 20 years.

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The toll was 40 cents for cars when the motorway opened in 1975, and even that was too high for some motorists, who continued to use the dangerous Old Princes Highway.

The toll was increased to 60 cents, and in 1992 to a $1.

Tolls were a hot issue at the 1995 state election.

The Labor Party, led by Bob Carr, scraped into government by promising to remove the tolls on the M4 and M5 motorways, as well as the F6.

In the wash up, the F6 toll was the only one to go.

Premier Carr blaming unforeseen tax problems for not being able to fulfill his promise on the M4 and M5, which were public-private partnership deals.

The state's longest-serving toll collector Colin Hagarty had mixed feelings on the day the F6 toll ended.

While Mr Hagarty, 46, enjoyed seeing the smiles of motorists as he waved them through, he was unhappy at having been made redundant.

Mr Hagarty had worked as a toll collector at Waterfall since the opening of the motorway.

"Toll collecting is my life," he told Fairfax reporter Daniel Lewis.

"I've watched whole families grow up from these toll booths.

"You never remember names, but you remember faces."

The motorway was described as "Australia's first computerised super road" when it was opened by Premier Tom Lewis in 1975.

The $28 million tollway featured an electronic driver-aid system, in which advisory speed, emergency and fog warnings were flashed on screens along the route.

Within weeks of the opening, sections of the road began sinking because of mining subsidence.

Gutters on the edge of the road buckled, sagged or were falling away.

Engineers were called in to organise urgent remedial action.