Only telltale sign to me would be an unusually clean tranny case and supporting linkages relative to the grime on the adjacent drivetrain components...otherwise, no way of telling w/o puling and inspecting...

__________________
2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car