Wow! this post is pretty old. Hope all is well w/TTMT's truck. I just wanted to add something that may be of interest and hopefully helpful.
When I first started out w/my old 64 Dart GT (back in early 70's, couldn't afford the 340 wedge I wanted) my neighbor suggested something to me after looking under the hood. He was a retired electrical engineer and had been around the block a few times more than me so I follow his simple instruction and ever since then have done the same to all my autos.
The instruction was; remove battery, clean dirt & grime from all 6 sides (top, bottom, etc. ) with soap & water, dry well, clean up posts until shinny with sand paper or whatever if you don't have post cleaning tool and re-install, secure the battery to the body. Take connections and clean like the posts. Here's what I would never have though of - throughly coat all contact surfaces with petroleum jelly then assemble, tighten and re-coat w/p-jelly.
The theory behind this (coating w/p-jelly), he explained, is "if air can't infiltrate, it can't corrode". As far as cleaning all sides of the battery, he explained "if there's no way for current to travel from + to - posts (via oils & grime) the battery will last longer and keep a good charge. Sometimes the simplest things are overlooked and are the culprits of demons.
As far as p-jelly - we now know about dielectric grease which is probably more suitable?
My $0. 02.