Stole uniform before time in submarine (1-4)
I believe the answer is:
u-boat
'submarine' is the definition.
('U-boat' can be a synonym of 'submarine')
'stole uniform before time' is the subsidiary indication.
'stole' becomes 'boa'.
'uniform' becomes 'u' (phonetic alphabet: alpha, bravo, charlie etc.).
'before' is a charade indicator (letters next to each other).
'time' becomes 't'.
'boa' put after 'u' is 'uboa'.
'uboa'+'t'='uboat'
'in' is the link.
(Other definitions for u-boat that I've seen before include "Submersible warship of WWII" , "Sea vessel" , "Take pool exercise" , "Submersible warship armed with torpedoes" , "German submarine of WW2" .)