Quins have now lost six of their eight league games this season, and their play-off hopes are already beginning to fade, but victory reignited Sale's prospects of a top-four finish.
The visitors led 17-12 at half-time through tries from Marcus Smith and Jack Walker.
But Sale, who scored through Alex Wills and Luke Cowan-Dickie in the first half, ran riot in the second half.
Jacques Vermeulen scored twice in quick succession to seal the bonus point before Rekeiti Ma'asi-White, Raffi Quirke, and Nathan Jibulu also touched down as Sale ran in 31 unanswered second-half points.
Sale's third win of the season lifts them to seventh and within nine points of the top four.