A tandem power train assembly including an input member, a tandem output assembly, and an oscillation joint assembly drivingly coupled to the input member. The oscillation joint assembly is structured and arranged to drivably transmit rotation to the tandem output assembly through the oscillation joint. The oscillation joint includes an inboard bearing defining a first frustoconical ring having a first bearing surface disposed thereon and an outboard bearing defining a second frustoconical ring having a second bearing surface disposed thereon with the inboard bearing and outboard bearing structured and arranged to rotatably support the tandem output assembly.