Green’s Dictionary of Slang

(US black) machine, usu. a car or a motorcycle.

1945		C. Himes If He Hollers 42: ‘He work on a ‘chine down in de back end’ [i.e. of a workshop].
1973		Cincinnati Enquirier (OH) Mag. 14 Oct. 44/2: ’Chine — a car.
1988		W.D. Myers Scorpions 39: ‘Why you got to lean on my ‘chine?’ Jamal looked at the car, then got off of it.
1988		W.D. Myers Fallen Angels 113: [of an M-60 machine gun] Johnson had the pig, the big sixty, the heavy ’chine.
1996		W.D. Myers Slam! 73: [of a Mercedes] That’s the way to live, my man.’ ‘Drive around in a big ‘chine like this’.