Their first and signature hit was "Shotgun," written and composed by Jr Walker and produced by Berry Gordy, which featured The Funk Brothers' James Jamerson on bass and Benny Benjamin on drums. "Shotgun" reached No. 4 on the Billboard Hot 100 and No. 1 on the R&B chart in 1965, and was followed by many other hits, such as (I'm A) Road Runner," "Shake and Fingerpop" and covers of the Motown tracks, "Come See About Me" and "How Sweet It Is (To Be Loved by You)".
The hits continued apace with tunes such as "I'm a Road Runner" and "Pucker Up Buttercup".
In 1969, the group had another hit enter the top 5, "What Does It Take (To Win Your Love)" A Motown quality control meeting rejected this song for single release, but radio station DJs made the track popular, resulting in Motown releasing it as a single, whereupon it reached No. 4 on the Hot 100 and No. 1 on the R&B chart. From that time on Walker sang more on the records than earlier in their career. He landed several more R&B Top Ten hits over the next few years, with the last coming in 1972. In 1979, Walker went solo, disbanding the All Stars, and was signed to Norman Whitfield's Whitfield Records label but he was not as successful on his own as he had been with the All Stars in his Motown period.
Consequently, Walker re-formed the All Stars in 1980. .
Junior Walker died of cancer at the age of 64, in Battle Creek, Michigan, on November 23, 1995. He had been inducted into the Rhythm and Blues Foundation that year. Junior Walker is buried in Oak Hill Cemetery, in Battle Creek, Michigan, under a marker inscribed with both his birth name of Autry DeWalt Mixon, Jr., and his stage name Jr. Walker. "Shotgun" was inducted into the Grammy Hall of Fame in 2002. The band carried on performing after his passing and continue to keep his legacy alive.