The band's fourth album, Girls, Girls, Girls, was released in May 1987 and debuted at number 2 on the Billboard 200. Sixx has said in interviews that he believes the album would have debuted at number 1 if not for behind the scenes maneuvering by Whitney Houston's record label.[52] The band again changed their look for the album and subsequent tour, trading the glam elements of the previous album for a biker aesthetic. he band faced many of the same personal issues that plagued the recording of Theatre of Pain and Sixx has complained that those issues compromised the album's quality, although he has spoken more positively about the record in subsequent years. After finding sobriety in 1989, Mötley Crüe reached its peak popularity with the release of their fifth album, the Bob Rock-produced Dr. Feelgood, on September 1, 1989. Rock and the band recorded the album in Vancouver, with the band members recording their parts separately for the first time to reduce infighting and to focus on individual performance. Aerosmith lead singer Steven Tyler who was recording the album Pump at the same studio, provided backing vocals. On October 14 of that year, it became a No. 1 album and stayed on the charts for 114 weeks after its release. The band members each stated in interviews that, due in no small part to their collective push for sobriety, Dr. Feelgood was their most solid album musically to that point.The title track and "Kickstart My Heart" were both nominated for Grammys in the Best Hard Rock Category in 1990 and 1991, respectively, but lost both years to songs by Living Colour. The band did find some success at the American Music Awards, as Dr. Feelgood was nominated twice for Favorite Hard Rock/Metal Award, losing once to Guns N' Roses' Appetite for Destruction, but winning the following year, beating out Aerosmith's Pump and Poison's Flesh & Blood. Mötley Crüe was also nominated twice for Favorite Hard Rock/Metal Artist.