Turn over a vehicle in the morning β it rattles! (6)
I believe the answer is:
maraca
'it rattles' is the definition.
(rattling instrument)
'turn over a vehicle in the morning' is the wordplay.
'turn over' is a reversal indicator.
'vehicle' becomes 'car' (car is a kind of vehicle).
'in the morning' becomes 'am'.
'a'+'car'+'am'='acaram'
'acaram' back-to-front is 'MARACA'.
(Other definitions for maraca that I've seen before include "'Hand-held percussion instrument, hand-held (6)'" , "One of a pair used by Spanish dancer" , "One of a pair of hollow pieces of wood or bone for Spanish dancing" , "Rattle used as a rhythm instrument" , "Percussion instrument played in pairs" .)