The Portland, Oregon native was a short-lived member of Dr. Mastermind, featuring former Wild Dogs vocalist Matt McCourt, before joining his brother, vocalist Tim Lachman, in another local band, Gargoyle, in 1988. Gargoyle would move to Los Angeles, California in 1990 where the band morphed into State of the Art recording an acclaimed three-song demo before disbanding in 1993. The Lachman brothers next hooked up with Canada native Shane Gaalaas, then the drummer for Swedish guitar virtuoso Yngwie Malmsteen, and recorded another demo under the name Eleventh Hour. In 1996, Lachman and Gaalaas teamed up with former Last Rites and World In Pain members A.J. Cavalier and Jeff Mohr to form Diesel and cut a 6-song demo. Parting ways with Mohr and adding Rich Gonzales, formerly with Recipients Of Death, on bass, the band would change their name to Diesel Machine in time for the release of their debut album, Torture Test, in 2000. By then Lachman had already been picked as one of the guitar players for Halford, the solo band of then ex-Judas Priest vocalist Rob Halford. With Halford, Lachman co-wrote and recorded Resurrection, Live Insurrection, and another studio album, Crucible. Lachman also collaborated with Tommy Victor of Prong on the song 'Initiation' which appeared on the band's 2002 100% Live album and was re-recorded as 'Embrace the Depth' for Scorpio Rising. 2003 saw the release of a Halford EP titled Fourging The Furnace, released in Japan only. That same year Rob Halford announced that he would return to Judas Priest. Lachman had already left the Halford band in November 2002 to join former Pantera guitarist "Dimebag Darrell" Abbott and his brother, drummer Vinnie Paul Abbott, in a new band called Damageplan as their vocalist. Their debut album, New Found Power, was released in 2004; in addition, the song "Ashes to Ashes", featuring Jerry Cantrell of Alice In Chains, appeared on soundtrack. The band had recorded several songs for a second album, however on December 8, 2004 during a Damageplan show at the Alrosa Villa in Columbus, Ohio, Darrell was fatally shot on stage by 25-year-old mentally ill ex-Marine Nathan Gale, who was shot and killed by police officer James Niggemeyer minutes later. After the untimely demise of Damageplan, Lachman put together a new band called The Mercy Clinic in 2005 with guitarists Brian Harrah and Josh Stinson, bassist Steed Najera, and drummer Bevan Davies. Over the course of the next couple of years the group would write and demo upwards of 20 songs and played frequent shows in the L.A. area but ultimately failed to land a record deal. Subsequently, the project was put on hold. On February 18, 2005 Lachman performed with the surviving members of Alice in Chains at a benefit for tsunami relief in Seattle, Washington filling in for their late lead singer Layne Staley along with fellow vocalists Maynard James Keenan, Wes Scantlin, and Ann Wilson. Lachman filled in for Killswitch Engage's guitarist Adam Dutkiewicz on the band's North American tour in early 2007. He also filled in for Dutkiewicz at Download Festival 2007. In 2008, Lachman began working with Raymond Herrera and Christian Olde Wolbers formerly of Fear Factory under the name Burn It All. On April 1, 2019, Lachman and Diesel Machine released "Shut It", their first new song in nearly two decades, and announced a tentative fall 2019 release for their long in the works sophomore album, Evolve. The album was finally released on August 21, 2020 through German company Metalville.