Good advice so far. Remember that there are many different types of trailers: flatbed, dump, cargo, cattle, horse, RV, etc. A hard sided RV is more difficult to tow than the other types. They have a huge frontal area, a high percentage of tongue weight, very little ability to shift the tongue weight, and a big side area to act as a sail. You can't just assume that a manufacturer's television ad stating a certain tow capacity is automatically applicable to every trailer type. A truck that might easily handle an 8,000 pound boat might be over-matched by a 7,000 pound RV. Truck payload vs. tongue weight is usually a much larger factory than tow rating; particularly with 1500 trucks. Looking at the door sticker payload and computing backward to a trailer tongue weight and gross weight is critical.