"It doesn't matter if you're an owner-driver trying to run a small business or a massive multinational company like Toll Group, Sydney's toll roads are simply too expensive," Mr Olsen said.

Despite the unions claims, Australia's biggest freight company, the Toll Group, would neither confirm nor deny a report that it had instructed its drivers to avoid toll roads because of the cost.

Instead, it appears the company uses a combination of both toll and non-toll roads while looking for the "most cost-efficient" route.

"Toll (Group) does not have a policy to avoid the use of road tolls," a company spokesperson said.

"We regularly undertake route optimisation reviews where we use data from previous trips to determine the quickest and most cost-efficient route for our drivers. In addition, Toll uses a mix of public and private toll roads to maximise time and cost efficiencies."

This week, the NSW Parliamentary inquiry looking into tolls was shown what was said to be a memo to Toll Group drivers accessing Woolworths site at Minchinbury and dated May 2021, which stated, "We thank you for your co-operation in reducing toll road use. This is a reminder to ensure you are not using toll roads unless you have the authorisation to do so. In most cases, the cost of the toll roads outweighs any benefit we receive from using them."

NSW Opposition leader Chris Minns tweeted, "This is the reality of the Government's obsession with toll roads. Trucks that can't afford to use our roads. And ruined local streets. Toll roads were supposed to get traffic off our streets. Instead, we have more trucks, more congestion and more noise."

NSW Shadow Minister for Roads John Graham said the memo provides an explanation for why the streets in the M5 corridor have been flooded with trucks.

Recent data from Transurban indicated 6,000 fewer cars and trucks are using the combination of the M5 East and M8 than used the M5 East alone seven years ago, simply because the new tolls that came in last year are too expensive, he said.

"One of our biggest freight companies and individual drivers have come to the same conclusion - the cost of using Sydney toll roads is just too high," Mr Graham said.

"The result is truck chaos on suburban streets. This is the opposite of what the public was promised. These toll roads were supposed to get traffic off our streets; instead, we have more trucks, congestion, and noise.

"We now know why B doubles are on Bexley Road. Tolls are too high.

"This directive is further proof. No wonder they are on suburban streets up and down the M5 corridor.

"Major freight operators scrutinise every dollar of their costs. The fact Toll has concluded toll road benefits don't stack up shows the Government has this policy wrong."