A mechanical tensioner for a traction drive element is provided. It includes a housing with a bore having an open end and a closed bottom. A plunger having a first end is located in the bore. The first end of the plunger has a tapered slot or tapered opening defined therein forming a hollow wall portion of the plunger. The hollow wall portion is discontinuous in a circumferential direction. A wedge insert is located at least partially in the slot or opening. The wedge insert has an outer surface with a contact area that is complementary to the tapered slot or tapered opening. A spring is located between the wedge insert and closed bottom of the housing. The spring forces the wedge insert into the tapered slot or tapered opening with an increase in force as the plunger is depressed into the bore in the housing. This forces the hollow wall portion outwardly in order to provide a friction damping feature that increases with the distance that the plunger is depressed.