arp-I've been reading the thread you started. I was planning on replacing the tires this spring, but before we went on vacation last fall I noticed the right rear tire was all of a suddenly worn on the outer edge like yours. I keep a close eye on tire pressure so that wasn't the problem. I'm wondering if the spring bushings are worn can it cause abnormal tire wear.
2003 GMC 2500 HD 8.1 & ALLISION TRANSMISSION
2000 SIERRA 30 ft FKSS