Hi Paula,
For you 2016 Freightliner 2500 with step bumper, I suggest using the etrailer Custom Trailer Hitch with 2" Receiver part # e82TR. It is a 2" trailer hitch receiver that will fit both the 144" and 170" wheelbase, however, it will NOT fit passenger vans or vehicles with a 30 3/8" frame measured from outside frame to outside frame. It is a no drill installation and is designed to sit at the edge of the step bumper, so you won't need an extension to get past the step.
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