Hauser drove a cab to support himself while pursuing a music career. Through this job, he met Laurel Massé, a waitress and aspiring singer. He was again driving his cab when he picked up the conga player for the group Laurel Canyon who invited him to a party where he met Janis Siegel. With Massé they reformed The Manhattan Transfer. They needed a male singer, so they contacted Alan Paul. The four became The Manhattan Transfer on October 1, 1972. After a car accident, Massé decided to leave the group and pursue a solo career, and in 1978 Cheryl Bentyne was hired to replace her. From then until Hauser's death, the line-up was mostly unchanged with only occasional substitutions due to illness. After his death, he was replaced by Trist Curless.