Switch gear? (5)

I believe the answer is:

shift

I believe this clue is a double definition.

'switch' is the first definition.
(I know that switch can be written as shift)

'gear?' is the second definition.
(I've seen this before)

(Other definitions for shift that I've seen before include "Simple dress; spell of work" , "underskirt" , "Move; work period" , "Change position" , "Move; loose dress" .)

I've seen this clue in The Globe and Mail.

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