On a cold start the engine is somewhat noisy, not much noisier than other 700's ive heard but a good amount. When I pull in the clutch the noise doesn't necessarily get louder but the pitch changes for a moment. After the engine is fully warm it purs. I know the noise is coming from the clutch because I used a mechanics stethoscope. No slippage, no problems with the clutch otherwise. Given its an 06' and never been apart, should I still pull the cover and investigate? Maybe throw in a new clutch with the full fiber mod? I'm just wondering if I am catching something early? I don't remember it making this noise with the rotella I was running (just switched back to Mobil 1 4t because it was on sale). Any opinions?