2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/170524We continue our study of residual properties of mapping tori of free group endomorphisms. In this paper, we prove that each of these groups are virtually residually (finite $p$)-groups for all but finitely many primes$p$. The method involves further studies of polynomial maps over finite fields and $p$-adic completions of number fields.11 pages, version 1: Comments are welcomeGroup TheoryNumber Theorytext