Campaigns to overhaul used cars (8)
I believe the answer is:
crusades
'campaigns' is the definition.
(crusading is a kind of campaigning)
'overhaul used cars' is the wordplay.
'used cars' can be anagrammed to 'CRUSADES'.
However, I'm unsure how this is indicated.
'to' is the link.
Can you help me to learn more?
(Other definitions for crusades that I've seen before include "wars" , "Military expeditions by Christians to recapture the Holy Land" .)