So I've been trying to figure out what exactly this piece is called as on one side of my truck it's rusted really bad as I've attached pictures of both sides. It's some kind of bolted-on support beam or crossmember, but when I look those up online it doesn't pull up anything of the sort. I put some POR-15 on both of them (that's why they're glossy) but I'd probably be better off buying a new set. It's a 2006 GMC Sierra 4.3