Your 2008 Mercury Mariner can be equipped with either a 1-1/4-inch Class II or a 2-inch Class III trailer hitch. There are many towing-type bike racks available for use with 2-inch hitches however there are no towing racks offered for use with Class II hitches that have a 1-1/4-inch receiver.
This is because the lighter-duty Class II hitches do not have the capacity required to handle the forces applied to the ball mount from an attached bike carrier.
Your options are then to either replace... view full answer...