First, it is cheaper and easier to get the proper towing package from the manufacturer. For pickups if it doesn't have a receiver - it doesn't have the upgraded towing package and I would not tow any high walled trailer. So find another example with the towing package. The included trans cooler is especially important.
Going from your 4.8L/4-spd to anything 2015+ will accelerate significantly better. With 6-8 speed transmissions and 50% more power from the 5.7L, or GM's 5.3L or Ford's 5.0L or Ecoboost, you'll be extremely pleased. So pick for favorite brand and get the proper towing equipment.
Ram does have the lowest payloads in the half ton class, so make sure the one you like has enough for your needs. Check out this sticker as test drive for as equipped payload.
