When you get your new cross member, coat it with Herculiner. It's similar to the spray on bed-liner "stuff" only your roll it on with a foam brush or just brush it on. Keep it out of any bolt threads. Herculiner is availble at a lot of stores. Menards carries it for 28 dollars a quart (cheapest I've found). Once you have it coated, salt will attack the bolts and metal attached to it, but the cross member will be damned near impervious to corrosion and rock damage from the road.