Fire crews were called to the M55 following reports a double decker bus might be on fire
On arrival at the scene firefighters discovered the bus had suffered a mechanical fault but there was no fire.
The bus was on the hard shoulder of the eastbound carriageway between junction three at Kirkham and junction one at Broughton.
A Lancashire Fire and Rescue service spokesman said the bus had most likely suffered an engine failure.
Police and Fire Service staff worked to make the scene safe.
One lane of the motorway is currently closed. It is expected to re-open by 4.45pm.
Motorists are being warned to take extra care in case oil has been spilled on the carriageway