So you repacked your hubs?
You most likely tightened the cones too much. The cones should only be tight enough so that the is no lateral play in your hub, anything more is too much. After the cones are loosely holding everything together you take a cone wrench to
hold the cone while you tighten the lock nut.
For more info try here...
http://www.parktool.com/repair/readhowto.asp?id=105