Employ Aussie truck to tour the Italian islands (7)
I believe the answer is:
utilise
'employ' is the definition.
('utilise' can be a synonym of 'employ')
'aussie truck to tour the italian islands' is the wordplay.
'aussie truck' becomes 'ute' (Australian abbreviation for utility vehicle).
'to tour' indicates putting letters inside (to tour can mean to go around).
'the italian' becomes 'il' (the in Italian).
'islands' becomes 'is' (i is an abbreviation for island).
'il'+'is'='ilis'
'ute' going around 'ilis' is 'UTILISE'.
(Other definitions for utilise that I've seen before include "Find application or task for" , "Put into service, find application for" , "Put to use" , "Employ, make use of" , "Employ, do something with" .)