2024 Week 11: UC Davis (8-1) @ Montana (7-2) Last time Montana lost by more than 7 points at home was...
2018 when we cooked them 49-21.
Unless I missed something, before that you have to go back to 2012 when they lost to Montana St by 9.
EDIT: Arbitrary margin of victory but the last time before 2018 they lost at home by 14+ points was in 2005 to Cal Poly. And again, unless I missed something, but besides the two losses to UCD, the last time Montana lost by 16+ points at home was in 1990 to Idaho.