Socialist vehicle - favourite star treatment (3,6)
I believe the answer is:
red carpet
'star treatment' is the definition.
'red carpet' can be an answer for 'treatment' (I have seen 'special treatment' mean 'red carpet' so perhaps 'treatment' could also mean 'red carpet'). I'm not sure about the 'star' bit.
'socialist vehicle favourite' is the wordplay.
'socialist' becomes 'red' (red can informally mean a socialist).
'vehicle' becomes 'car' (car is a kind of vehicle).
'favourite' becomes 'pet' (synonyms).
'red'+'car'+'pet'='RED-CARPET'
Can you help me to learn more?
(Other definitions for red carpet that I've seen before include "sort of treatment for special visitors?" , "It's rolled out for special guests" , "special welcome" , "sort of deferential treatment?" , "see VIP on this?" .)