Cleaners and engineers for First Bus in south Staffordshire and south Cheshire struck over pay for seven days from 28 April to 4 May.
The action was taken after First Bus walked out of talks with the conciliation service Acas.
Some 82 percent of engineers and 75 percent of cleaners voted in favour of the strike action.
The week long strike has been followed by 62 depot workers, members of the T&G union, working to rule.
The union has said that if the bosses do not put a real offer on the table it will take further strike action.
The dispute centres on the fact that workers at First’s sites in Adderley Green, Stoke-on- Trent, Newcastle-under-Lyme and Crewe are paid considerably less than depot workers in Chester.
Engineers for First in North Staffordshire and South Cheshire earn £7.52 an hour, compared with £9.25 for those in Chester. Cleaners earn just the minimum wage in most of the region, but £6.19 in Chester.
T&G regional organiser Neil Salter said, “There will be a summer of discontent. It can be resolved by negotiation, but with the company walking out of talks, we will have no reason but to prosecute other measures vigorously.
“We reserve the right to take further strike action, and will review our position on a week-to-week basis.
“The company has shown contempt and arrogance so far by its ‘take it, or leave it’ approach. We are willing to negotiate, but it takes two to tango.
“Having stood on the picket line with our members I know that their spirits are high.
“What our members want is the same pay for doing the same job.
“Having spent months and months in negotiations without agreement our members now have no alternative but to fight back for a fair deal on pay.”
The union has already rejected a two-year offer that would still have left the workers on lower rate than other regions.
First Bus drivers at the depots where the engineers and cleaners are currently in dispute last year won a 21 percent pay rise after taking several days of strike action and recruiting over 150 new members to the union.
Cleaners and engineers at the time supported the drivers’ campaign and it is important that solidarity across the depots continues.
Last year’s strike, and the unity and success that came from that dispute showed the depot workers that they could fight and they could win.