Does your truck burn oil? If so, I'd go with a high mileage oil (with 80k, I doubt you would, but it wouldn't be unusual if you did.)
Also, check your manual, it will tell you the BEST oil weight you can run... I know when Dodge started their "4-cylinder shutoff" they started recommending the use of 5w-20. I'm not sure if your truck uses that, but if it does, then I'd go with the 5w-20 so you don't get any engine problems.
As for brand, as long as you're going full synthetic, you really can't go wrong. Certain enthusiasts will swear by one brand name or the other, but for the most part, they're all pretty similar. I personally use Mobil 1 and/or Royal purple. I know they're a bit costly, but since I drive it like I stole it, I think I can justify the cost.
Hope this helps!