Figure the short answer to be 'trucks' (4)
I believe the answer is:
vans
'be trucks' is the definition.
(I've seen this in another clue)
'figure the short answer' is the wordplay.
'figure the short' becomes 'v' (I can't explain this - if you can you should give a lot more credence to this answer).
'answer' becomes 'ans' (abbreviation for answer).
'v'+'ans'='VANS'
'to' is the link.
Can you help me to learn more?
(Other definitions for vans that I've seen before include "Transport" , "Trade vehicles" , "Goods vehicles" , "Commercial vehicles" .)