It's free at the garage (3)
I believe the answer is:
air
'it's free at the garage' is the definition.
I can't judge whether this defines the answer.
'it's free at the garage' is the wordplay.
'it' becomes ''t' (abbreviation. e.g. in 'tis).
'free' indicates named letters should be taken away (the word is freed of certain letters).
'the garage' becomes 'ir' (I can't justify this - if you can you should believe this answer much more).
'at' with 't' taken away is 'a'.
'a'+'ir'='AIR'
Can you help me to learn more?
(Other definitions for air that I've seen before include "Mix of gases surrounding the earth" , "a life support" , "Spread publicity" , "Bearing, manner" , "piece of music" .)