Unbalanced tires?

[zeropointbug]

Hey guys.... I got my Revo up and running after a long winter, runs great... except that the tires are way out of balance for some reason?! Both my RD Logic porcupines, and Badlands. I'm thinking that running full throttle through the snow had something to do with this. But I have checked for water in the tires, and the foam inside feels even. I am having troubles with the 6mm lock nuts coming off and the tire flies off because of this (from vibration). I doesn't seem to affect handling a whole heck of a lot, but at high speed, I can feel it, and see it somewhat.

Any ideas? thanks.