A transport lobby group in Birmingham has asked the city council to rethink its decision to restore bus lanes on a road after five months without them.
The bus lanes on the A38 Tyburn Road in Erdington were suspended in July to ease congestion, while repairs were carried out on the nearby M6 motorway.
The West Midlands Business Transport Group says traffic has moved well since the lanes were suspended.
But bus operator Travel West Midlands says passenger numbers have dropped.
The company claims they have dropped by 15% on the Tyburn Road since the bus lanes were stopped.
Highway officials opened them to other traffic as a temporary measure.
The closure of Junction 6 during roadworks on the M6 meant there was an increase in traffic on the A38 route.
The transport group has written to the city council asking it to ensure that re-introducing the bus lanes would be an overall advantage.