The most common and most likely answer to this crossword clue is the 4 plus 3 plus 2 plus 4 letter word CANT BUY ME LOVE
C
A
N
T
B
U
Y
M
E
L
O
V
E
Buddy explains!
The straight part
We know that "Successful old track" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case successful old track = cant buy me love.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.