Dalton completed 12-of-20 passes for 189 yards, two fourth-quarter touchdowns and one interception.
Turner scored once in the third quarter after 19 carries for 79 yards.
The Horned Frogs (4-0) hold a 43-39-7edge in the all-time series.
SMU quarterback Bo Levi Mitchell went just 17-for-38 passing for 240 yards, two touchdowns and two interceptions.
Wide receivers Emmanuel Sanders and Shawnbrey McNeal caught scoring passes, but the Mustangs (2-2) netted -16 rushing yards and lost two fumbles.
They trailed only 12-7 at the half.