Either residual oil in the air line/ solenoid or new seals are torn too. As for why the new seal could be bad... Could be install error, burr tore it, or loose preload in the bearings allowing the locker to shift side to side wearing on the seal.
That's assuming you checked common stuff such as the vent not blocked and allowing diff to pressurize. Eta, didn't see that you already checked it
Last edited by bthomas; 11-30-2013 at 06:19 PM.