In deep snow you will wallow from side to side if the rigs in front are not exactly the same size as you are, or if you are not following directly in their path.
You never mentioned having an alignment done. I am guessing all the work you have done it would be included.
New wheel bearings need to have been torqued 150 psi. Wouldn't be more noticeable in the snow, but needs to be at least minimum of 125 psi.