Mac crashed into a car (8)
I believe the answer is:
raincoat
'mac' is the definition.
(I've seen this before)
'crashed into a car' is the wordplay.
'crashed' indicates anagramming the letters.
'into'+'a'+'car'='intoacar'
'intoacar' with letters rearranged gives 'RAINCOAT'.
(Other definitions for raincoat that I've seen before include "Outer garment for Croatian" , "Catriona (anag.)" , "Water-resistant outer garment" , "Wet weather wear" , "Wet weather gear" .)