Renault changed gear (7)
I believe the answer is:
'gear' is the definition.
(I've seen this before)
'renault changed' is the wordplay.
'changed' is an anagram indicator.
'renault' with letters rearranged gives 'NEUTRAL'.
(Other definitions for neutral that I've seen before include "trying to keep out of the war" , "Gear position" , "On the fence" , "not getting involved?" , "'Neither good nor evil, nor right nor wrong (7)'" .)