Needed when driving fresh clothes? (4-6)

I believe the answer is:

gear-change

I'm a little stuck... Click here to teach me more about this clue!

'needed' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'driving fresh clothes?' is the wordplay.
'driving fresh' becomes 'gear' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'clothes?' becomes 'change' (change is a kind of clothes).
'gear'+'change'='GEAR-CHANGE'

'when' is the link.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.