Following Ruffin's departure, Whitfield began to rework the group's sound and pushed them further into progressive rock and psychedelic soul, although ballads were still recorded as B-sides and album fillers. The group's sixth album, Surface Thrills, was a significant step in this direction, and one that did not meet with the approval of the remaining members.
At the same time, Eddie Kendricks was becoming restless with his role in the group, particularly as Paul Williams' health continued to decline. In addition, he was angry over Otis Williams' control of the group and was convinced that Motown was cheating them out of money. Kendricks was replaced with Dennis Edwards, a former member of the Philadelphia band the Contours who had impressed both Eddie and Otis during a tryout at a Detroit club.
The Reunion tour that followed was successful, but the group's future remained unclear. Kendricks and Edwards made plans to continue performing as a duo, but those plans were scuttled after the death of Ruffin on June 1, 1991, in Philadelphia. He had been suffering from a series of strokes.