Rear Side Window rattle

[BigRed76]

I finally isolated the annoying rattle I hear every time I go over a bump. It seems as though my rear side elongated large window is a bit loose. How do I go about tightening it??

 

[Kerrville15]

I had the same issue on my wife's yukon. I found that the little plastic piece was rattling against the window so I put a strip of foam tape in between the two pieces & it solved the problem.