In the 1920s and 1930s, jazz musicians said keep on truckin'. You can see an example of it near the end of the 1940s cartoon Dumbo, where one of the crows says "I even saw a vegetable truck," and all the crows assume the Keep on Truckin' position.
Truckin' on down the line
Hey hey hey
I say keep on truckin' Truckin' my blues away.
Keep on truckin' mama
Truckin' my troubles away.
I say keep on truckin' mama
Truckin' my troubles away.
Do that thing you do so well
I can tell what you been doin'
By the way that you smell.
Keep on truckin' mama
Truckin' my troubles away.
An extremely popular 1960's hippie saying that was made ubiquitously famous by the one-of-a-kind, extremely esoteric and eventually iconic comic strips and books which appeared and evolved from within the exquisitely unique mind of the mad-genius cartoonist R. Crumb. These three simple words of encouragement reinforced the then-prevailing idea that people should be able to feel confident about staying true to their own chosen life path and not allowing the outside world to get them down or force them to change who they wanted to be.
"Whether or not that peace march you're going on does anything to stop the war or not, just remember to keep on truckin'!"