1. "Posi" traction is always good over a open rear end differential. Most of it is traction and momentum. If you can find it on ebay or a junkyard, a limited slip is a good upgrade. So are good meats, almost anything can do better than the stock tires. Plus two wheel burnouts are cool. :)
2. Performance or off-road endurance? Well you may have meant off-road performance instead of endurance. Well that really depends on what you want. Performance mods will help your everywhere, and off-road mods only really help when you're off-road. Of couse a lift kit always looks good on the street too. So really the answer is both in equal measures.
3. Hard to say without any more details. If you click the quick links button on the toolbar, you can edit your signature to include more details about your truck. Stuff like engine size, transmission type, box configuration, and gearing can influence the answer to your question. Basically if you should be able to fit 31 or 32" tires with little to no fuss. (May take a little t-bar cranking or inner fender guard cutting) If it starts to bog down too much for you, you can change out the rear gear to return some pep.
4. Welcome to the site!!
Last edited by Mnemonic; 12-01-2004 at 03:00 PM.