Push new driver into digger (6)
I believe the answer is:
shovel
'digger' is the definition.
(I know that digger can be written as shovel)
'push new driver' is the wordplay.
'push' becomes 'shove' (shoving is a kind of pushing).
'new driver' becomes 'l' (learner drivers have L-plates on their cars).
'shove'+'l'='SHOVEL'
'into' acts as a link.
(Other definitions for shovel that I've seen before include "digger" , "Old clerical hat" , "Spade with a broad blade" , "Tool like a spade" , "Spade-like tool" .)