Load vehicle before work (5)
I believe the answer is:
cargo
'load' is the definition.
('cargo' can be a synonym of 'load')
'vehicle before work' is the wordplay.
'vehicle' becomes 'car' (car is a kind of vehicle).
'before' is a charade indicator (letters next to each other).
'work' becomes 'go' ('go' can be a synonym of 'work').
'car'+'go'='CARGO'
(Other definitions for cargo that I've seen before include "Ship's freight" , "Hold contents" , "This taken on board" , "Goods carried by vessel or vehicle" , "Goods carried on ship or plane" .)