Ramirez, previously assistant to former Mexico coach Sven-Goran Eriksson, replaced Omar Arellano, who was fired on Wednesday after only three matches at the helm.
"He knows the players, he has the discipline we are looking for and he can exercise leadership over the players," club president and owner Jorge Vergara told a news conference.
The change was announced three days before Guadalajara face arch-rivals America in the biggest fixture of the domestic season.
Arellano managed two draws and a defeat in his three games in charge before becoming the ninth coach to lose his job since Vergara bought the club in 2002.
Daniel Guzman, Hans Westerhof (twice), Xavier Azkargorta, Jose Manuel de la Torre, Benjamin Galindo, Eduardo de la Torre and Efrain Flores are the other coaches to have lost their jobs under Vergara.
Vergara, seen as a boastful upstart by the Mexican business establishment, said he would turn Guadalajara into the world's biggest club when he bought it in 2002.
He also co-founded Chivas-USA to draw on the large Mexican community in Los Angeles and also owns Costa Rican club Saprissa.
Guadalajara have won one Mexican title since Vergara took over in a country where two separate championships are played each season.
