Rio Grande Mud is the second album by the Americanrock band ZZ Top. It was released in 1972.
The album title was inspired by the Rio Grande, the river that forms the border between Mexico and Texas.
In 1987, the album was remixed for CD release. On January 11, 2011, Rhino released a remastered version from the original 1972 mix on vinyl only. This album was put up for download on Amazon.com's MP3 store and iTunes as a digital download in 2012, and features the original mixes of the tracks that are on Chrome, Smoke & BBQ, and the 1987 remixes of the tracks that are not from that boxset. The original mix of the album was released on CD in June 2013 as part of the box set The Complete Studio Albums (1970-1990).
AllMusic gave the album 3.5 stars stating: "With their second album, Rio Grande Mud, ZZ Top uses the sound they sketched out on their debut as a blueprint, yet they tweak it in slight but important ways."
The only single released from the album was "Francine" (b/w "Down Brownie") which peaked at number 69 on the Billboard Hot 100. Another 45 version was released with "Francine" appearing on both sides (side one with English vocals and side two with Spanish vocals). Various official ZZ Top releases throughout the years, beginning in 1972, have used the alternative spelling "Francene", especially on the various 45 releases both within and outside the United States. A song about romance with an underage girl, the lyrics contain lines such as "My Francine just turned thirteen, she's my angelic teenage queen, and I love her, she's all that I want."