Doing some searches on CF, and some way maybe the endlinks are bad, which mine are brand new from GMparts house along with the Z51 Sway bars, Some also say the bushings are making this popping or clanking sound. And they need to be greased?
Like from this guy on CF
"If it isn't the endlinks, it could also be the u-shaped brackets that hold it in place on each side.. there are bushings inside the brackets and the sway bar rotates inside it.. I had a popping noise that wouldn't go away same symptoms you all describe on my C5Z and I finally traced it to those bushings. I loosened them up, greased the surface and re-tightened them. Problem solved.. "
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Arctic White 97 C5 Coupe
NOT STOCK 
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