It's heavier springs on the front (pretty simple to exchange with basic handtools, decent floor jack and large jack stands). Dual batteries and the heavy duty alternator come with the plow prep as well (We already have them with the diesel). I'm not sure if there's anything else or not.

One thing I've been told, if you put a plow on a truck w/o plow prep package it will void warranty for any failure related to having the plow.