Ok so first things, sorry if this is a repost. I'm just not even sure what to search to hopefully answer my question. I'm currently doing, well pretty much every maintenance check off as I have no clue when anything was even done and I've already put 30k miles on my frontier. Alright so to the point, I have a 01 XE 3.3L 4x4 Manual trans king cab. I'm under it checking my brake lines as it would seem one or two of mine are in not great shape. Well while underneath I discovered what I first thought was a bump stop of sorts, only I don't know if it is. I have one of both sides and it's on the frame right where the cab and bed meet. I'll try and post a picture, but does anyone know what this is or does? It's encased on all sides, minus top and bottom, in metal with a tab that sticks out away from the frame. I've looked all around it and it just looks like some sort of rubber block that is just dead weight. Any help is greatly appreciated!