Politicians have demanded train operator Northern Rail compensate passengers who are forced to use outdated Pacer trains.
Greater Manchester mayor Andy Burnham, Sheffield City region mayor Dan Jarvis and Leeds City Council leader Judith Blake have expressed to the company their "deep disappointment and frustration" at news that the trains will continue to be used into 2020.
The letter signed by the three leaders and sent to Northern managing director David Brown said the firm should reduce fares on routes where Pacers are being used until their replacements are brought into service.
Mr Jarvis said the current arrangement was:
Pacers were introduced in the early 1980s as a stop-gap solution to a lack of rolling stock.
But their use has continued and Northern has said the trains will still be used in the Sheffield City region and some other routes into 2020.
The politicians said that the continued use of Pacers "underlines the widening disparity between transport investment in the north, compared to the south".
Ms Blake said:
Northern, which is owned by Germany-based Arriva, has been contacted for comment in response to the letter.
Last week, Transport Secretary Grant Shapps took the first step towards potentially stripping Northern of its franchise.
He told MPs he has issued a "request for proposals" from the firm and the Operator of Last Resort (OLR), which could lead to services being brought into direct government control and run by the OLR.
Giving evidence to the Commons' Transport Select Committee, he said the level of performance on the Northern network "cannot continue".
He went on: