After two years of recording, the Transplants issued their self-titled debut album on Hellcat Records in October 2002. In the end, the album was recorded and mixed entirely in Armstrong's basement. The album was recorded with a number of special guest vocalists, which included Eric Ozenne (The Nerve Agents), Davey Havok (AFI), Son Doobie (Funk Doobiest), Danny Diablo (Crown of Thornz, AKA Lord Ezec), Lars Frederiksen (Rancid) and Brody Dalle (The Distillers, ex-wife of Tim). Dalle sang on the track "Weigh On My Mind", which Armstrong, at the time, described as "their song." The Transplants embarked on a full-scale tour around the world to promote the album which earned the band critical and commercial success.
After the release of the self-titled album, the Transplants went on hiatus in 2003, due to all members being involved in their own projects, including Rancid and Blink-182. However, in 2004 during an extensive Rancid hiatus, Armstrong decided to bring the Transplants back together. They resurfaced with their second album Haunted Cities, which was released in June 2005, just four months after Barker's former band Blink-182 announced their hiatus. The album's first and only single, "Gangsters and Thugs" was a hit and the band began touring on the 2005 Warped Tour. After the Warped Tour, the Transplants started to plan a large North American tour with Pennywise and wanted to release a second single. The band had even shot a video for the upcoming single "What I Can't Describe." However, these plans were cut short due to Armstrong reportedly suffering from exhaustion.
Following the end of the Haunted Cities tour, the Transplants announced their second hiatus in 2006. Reasons for another hiatus were essentially the same as they were in 2003. In 2010, the band reunited and began working on new material. The first recording to show up was "Saturday Night", which appeared on Barker's solo album Give the Drummer Some. Their third album, In a Warzone, was released on June 25, 2013.