A couple weeks ago I pulled bunny wabbit into the shop and changed the oil and t-stat, didn't touch anything else...ok so I might've sorta touched other stuff

. When I took it out a few hours later I hadn't gone 100 yards and I could hear this tapping sound, it sounds like it happens every wheel rotation.
I first hear it at about 15mph and then I can always hear it in any gear that goes fast enough, swerving back and forth (so the tires kinda howl) has very little affect and after driving 55-60mph for 15 minutes the bearings are still ice cold.
I just put up with it for a while hoping it would go away but it didn't (duh

) so I took it back in, jacked it up and wiggled, spun and shook the tires and the only thing I could find was the drivers side ball joint was bad so I changed it and the same side front wheel bearing was maaaybee slightly noisy.
I've heard bad wheel bearings though and there wasn't much noise there besides the dragging disk brakes.
I did go over the tires and make sure I didn't have a nail poking out and tapping the road so that's ruled out.
and it better not be the tranny!!!!!! I checked the tranny oil and it was plenty good, according to this
http://www.brokevw.com/020oil.html the rabbits don't need the extra .5L of gear oil which means mine's overfilled.
If anyone has a clue of what this could be I'd appreciate it