Consider changing gear on the road (6)
I believe the answer is:
regard
'consider' is the definition.
(I know that consider can be written as regard)
'changing gear on the road' is the wordplay.
'changing' is an anagram indicator.
'on' says to put letters next to each other.
'the road' becomes 'rd' (abbreviation).
'gear' with letters rearranged gives 'rega'.
'rega'+'rd'='REGARD'
(Other definitions for regard that I've seen before include "given respect" , "Look at - estimation" , "Concern" , "Attitude of admiration or esteem" , "Consider; gaze at" .)