gear change
US /ˈɡɪr tʃeɪndʒ/
UK /ˈɡɪr tʃeɪndʒ/

1.
a change to a different gear ratio in a vehicle or bicycle
:
•
He made a smooth gear change as he accelerated.
•
The car needs a new gear change mechanism.
2.
a significant change in a situation or plan
:
•
The new CEO announced a major gear change for the company's strategy.
•
We need a complete gear change in our approach to customer service.