| Couple pics went down and couldn't edit the OP so:
Differential output seals
These normally won't pour fluid or leave a leak on your driveway. But you will notice the leak if you get under the car and look at the diff. They leak slowly and build up residue under where the axles bolt to the diff. This is what it looks like when one is leaking.
This one is new with the pulley and belts removed, but it will be leaking from below this area.
Last edited by 330ciandr6; 03-01-2013 at 09:27 AM.