Most vehicles with "Towing packages" include an oil and transmission cooler. Most, Not all. So check to see if you have them. If not, I would add them as keeping those lubricants cooler and not breaking them down IS the safeguard to not damaging the engine and tranny.
Checking your payload number on the drivers side door sticker against what your tongue weight, passengers, hitch weight and anything else you add to the truck in the cab or bed will tell you if you have miscalculated and have too much trailer for your truck.