I got that off-black Cadillac, midnight drive
Got that gas pedal, leaning back, taking my time
I’m rolling that roof off, letting in sky
I shine, the city never looked so bright

from Macklemore and Ryan Lewis (Ft. Macklemore & ScHoolboy Q) – White Walls Lyrics on Rap Genius

Meaning

He’s probably ridin around in something like this

He’s in no hurry, so the gas pedal is “leaning back” rather than touching the floor. Alternatively, leaning back is the position he is sitting in when he is driving, meaning he is chilling. Much like the Gangsta Lean.

The use of the phrases “Gas Pedal” and “Leaning Back” could be references to Sage the Gemini’s Gas Pedal and Fat Joe’s Lean Back.

Just a suggestion, needs still more research though.

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