Dennis,
And I can see this happening too, from the bike rack being unsecured,
rocking back and forth on the hitch.

But mine doesn't swing and sway, because I secure the bike rack when
loaded, to the bottom of the bumper, with Ancra tie downs, and pull it
tight.

No swaying----no swinging,
no rocking----- no rolling.
no breaking.

Later,

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Terry
74 Campmobile (Clementine)
85 GL
86 BMW 325 ES