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For your 2017 Cadillac CT6 I recommend the Curt Trailer Hitch Receiver - Custom Fit - Class II - 1-1/4" # C12160 which has a tongue weight rating of 350lbs and a towing capacity of 3500lbs. You will want to check your vehicles owner's manual to find its towing capacity, and use the lower rating between the hitch and vehicle.
To tow a trailer you will need a vehicle wiring harness # C56323, Drawbar # C45521, and 1-7/8" hitch ball # 19256 or 2"... view full answer...