Hope everyone isn't pissed at the world for the hour forward last night, but happy Sunday regardless. I recently had a Flowmaster y-pipe with dual cats to replace the factory set up as the check engine light was on for bad cats. So far I noticed much better flow, but also a strange metallic sound. When driving only, it sound like someone is shaking a can of spray paint. It is very noticeable when I don't have the radio on. After checking for clearance issue, I could not spot anything. This only started after the installation of the y-pipe (local muffler shop installed it). This morning I took I to one of their sister stores and the mechanic said he could not find anything that could be causing the sound. He check the clearance and even tapped everything with a hammer and still nothing. I'll be calling Flowmaster on Monday to report the issue. Kinda ranting here but does anyone have an idea what could possibly be creating the sound? - - - Updated - - - I'll give them a call in the a.m. tomorrow. Didn't know if anyone had a similar run in or an idea.