What was the most popular song from the second Van Halen album to feature vocalist Sammy Hagar?
When It's Love:  It was released as a single from their album "OU812". OU812: OU812 (pronounced "Oh You Ate One Too") is the eighth studio album by American hard rock band Van Halen, released in 1988, and the second to feature vocalist Sammy Hagar.
i don't know