Vehicle runs on the tankers' contents (7)
I believe the answer is:
cargoes
'the tankers' contents' is the definition.
The answer and definition can be both man-made objects as well as being plural nouns.
Perhaps they are linked in a way I don't understand?
'vehicle runs on' is the wordplay.
'vehicle' becomes 'car' (car is a kind of vehicle).
'runs' becomes 'goes' ('go' can be a synonym of 'run').
'on' says to put letters next to each other.
'car'+'goes'='CARGOES'
Can you help me to learn more?
(Other definitions for cargoes that I've seen before include "Ships' loads" , "Carried loads" .)