My S-Trim was just recently installed. I know the belt had to be tighter than it was, so this evening, and friend and I tightened it. While doing so, we first snapped an extension in half After getting the piece out, we tried again. My friend, who was tighening the belt while I got the bolts said he felt like it was slipping. After removing the extension, sure enough you can see where the extension was starting to spin in the hole. Has anyone experienced this?