What sensibilities from postmodernism does Dieselpunk borrow from?
Dieselpunk: Dieselpunk is a genre similar to that of its more well-known cousin "steampunk" that combines the aesthetics of the diesel-based technology of the interwar period through to the 1950s with retro-futuristic technology and postmodern sensibilities. Postmodernism:  While encompassing a broad range of ideas, postmodernism is typically defined by an attitude of skepticism, irony or rejection toward grand narratives, ideologies and various tenets of universalism, including objective notions of reason, human nature, social progress, moral universalism, absolute truth, and objective reality.
an attitude of skepticism, irony or rejection