Road markings near entry points for Sydney's new M4 East road tunnels have been improved in an attempt to reduce the number of motorists mistakenly taking the wrong lanes, ahead of an expected surge in traffic volumes on Tuesday when public schools reopen to students.

Transport officials have decided to refer to Parramatta Road on lane markings as "Parra Rd", instead of its road number A44, because of the confusion it has caused motorists navigating a westbound entry point for the M4 East tunnels at Ashfield in the city's inner west.

The enhanced road markings in Ashfield are brighter and refer to "Parra Rd" instead of "A44". Credit:Kate Geraghty

The instances of motorists stopping in lanes or reversing to avoid copping tolls on the M4 East tunnels – the first major stage of the $16.8 billion WestConnex toll road – and instead taking Parramatta Road, had declined over the past week, officials said.

Ahead of a surge in traffic volumes of up to 20 per cent on Tuesday due to schools reopening, Roads Minister Andrew Constance urged motorists to continue if they mistakenly ended up heading onto the new roadway, and not make risky manoeuvres to avoid it at the last minute.