Liberal must get drug after I'd run out of gear (4)
I believe the answer is:
idle
'run out of gear' is the definition.
(I've seen this in another clue)
'liberal must get drug after i'd' is the wordplay.
'liberal' becomes 'l' (abbreviation).
'must get' means one lot of letters go next to another.
'drug' becomes 'e' (E is another name for ecstasy).
'after' says to put letters next to each other.
'l' next to 'e' is 'le'.
'le' after 'id' is 'IDLE'.
(Other definitions for idle that I've seen before include "Member of comedy team" , "Turn over" , "Tick over like engine" , "Lazy, doing nothing" , "Unoccupied or not in use" .)