My 4.7 has had an odd vibration since I've bought it. While idling, cold or hot, in drive or park, I get a noise that just sounds like the engine is louder, but almost has a bass like sound thru the entire truck. Also, holding the revs in park between idle and 2000, there's light vibration, 1200 rpm being the roughest spot.

I have changed the spark plugs because it needed new ones badly. No check engine light either, and besides this issue the truck runs like a top. Looking at the balancer while the engine is running I do see a noticeable wobble, however not so bad the tensioner is jumping around. Will a bad HB cause these symptoms I have?