"Knockin' Doorz Down" is the second single off Pimp C's second album Pimpalation.
In the music video, directed by Benny Mathews, the third verse is rapped by Pimp C instead of Lil Keke.
In the song, Pimp C raps about Houston's current status.
Houston hip hop artists Lil' Flip, Slim Thug, & Z-Ro are also mentioned.
He also talked about how Paul Wall & Chamillionaire breaking up and going separate ways.