Sheehan, who was found dead that morning after an apparent heart attack, worked with the Irish superstar group for more than 30 years. He had also worked with rock acts such as Led Zeppelin, Patti Smith and Lou Reed. He was 68.
Bono chose to honor Sheehan early on during the set at the Forum.
He described the band as a "brotherhood," after it had just torn through the classic post-punk cut "I Will Follow."
"The extended family is very, very important to us, and we look after each other," Bono continued. "Last night we lost a member of our family."
The crowd welcomed the shout-out with cheers.
"He loved, as we all do, the city of Los Angeles," Bono said. "He called the Sunset Marquis his home away from home."
Bono injected some levity into what could easily have been a heavier interlude during the second night of a five-night engagement at the Forum.
"He always thought that maybe U2 could be the next Led Zeppelin, which of course is impossible," the singer recalled.
The members of U2 once dressed up as the English hard-rockers for at a birthday party for Sheehan. U2 guitarist the Edge had come equipped with a double-neck guitar, a signature instrument for Jimmy Page.
"The biggest problem was, I couldn't quite fill Robert Plant's pants," Bono quipped.
Then he fittingly introduced the song "Iris," written for Bono's mother -- a piece meant to fill a void left by the loss of a loved one.
The band closed out the concert with "40," from the 1983 album "War," dedicating the performance to Sheehan.
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