Green’s Dictionary of Slang

1. dancing the truck.

1935		Amsterdam News (N.Y.) 31 Aug. 11/1: Who Originated the ‘Truck’? [...] Noble Sissle [...] titled a show at the Harlem Opera House in the winter ‘Trucking on Down’ and wrote a song with the same title.
1937		J. Latimer Dead Don’t Care n.p.: ‘Aw, come on, Camelia,’ called Miss Day, moving her torso slowly from side to side. ‘I’d like to do a litle truckin’.’.
1944		D. Burley Orig. Hbk of Harlem Jive 149: trucking: a dance introduced at Cotton Club in 1933.
1961		(con. c.1935) R. Poole London E1 (2012) 21: New and exciting gyrations known as [...] the Suzy-Q, and Trucking.

2. (US black) strutting, strolling.

1936		A.E. Duckett N.Y. Age 18 Jan. 7/1: [column heading] Truckin ’round Brooklyn .
1942		Z.N. Hurston ‘Story in Harlem Sl.’ in Novels and Stories (1995) 1010: Trucking: strolling.

3. moving, struggling along, getting on with it; esp. as in hippie n.² (3) slogan keep on trucking, an exhortation to continue with one’s life.

1972		Sat. Rev. (US) 28 Oct. 12: One poster [...] shows the famous R. Crumb cartoon characters and bears the caption: ‘Let’s Keep on Truckin’’.
1994		M. Ribowsky Don’t Look Back 52: This is not to say that those [negro league players] who kept on truckin’ in the shadows don’t deserve their romantic due; they certainly worked hard enough for it.
2008		T. Dorsey Atomic Lobster 32: Watch the sun come up, then keep on truckin’ into the next day.