Drives without a third and second gear (5)
I believe the answer is:
dress
'gear' is the definition.
(both can mean clothing)
'drives without a third and second' is the wordplay.
'drives' becomes 'res' (I can't explain this - if you can you should give a lot more credence to this answer).
'without' indicates putting letters inside (some letters go outside or 'without' others).
'a third and' becomes 'd' (srd letter of 'and').
'second' becomes 's' (common abbreviation).
'd'+'s'='ds'
'res' put inside 'ds' is 'DRESS'.
Can you help me to learn more?
(Other definitions for dress that I've seen before include "Clothing - groom" , "habit" , "Something made from fabric" , "Gown" , "Clothe; decorate" .)