G'day collective brains, I was driving my 3500s around town as normal, stopped for lunch and when I took off again suddenly I noticed a faint strange noise that seemed like coming from the right hand driver side fan/went. Then it got louder. I can only hear it when I accelerate, the harder I push it the louder it gets. It sounds like when you chuck a sheet of paper into a fan. It does it even when standstill if I just rev up the engine. Should I be concerned? What could it be? Supercharger maybe? Cheers Andrew