When wheels were turned hard left or right, wheel stop had worn a groove, which matched up only under certain load conditions. When it does not match up any motion or tap of brakes causes it to suddenly drop in place resulting in a sound like a sledge hammer had hit frame. (I did notice in previous posters' picture in background this same wear. Surface grinder to resurface contact area fixed problem. But this is casted metal contacting cast aluminun so it is not the final solution.
I am certain this is a common problem on all Jeeps with this design. see attached pic.
This is my 2010 Jeep Cherokee Problem started at about 36,000 miles
Rollem
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