It all depends on the weight of the tractor and the axle rating on the trailer and the load range of the tires on it (not to mention the condition of the tires themselves). The one set of brakes should be sufficient for cautious trailering if your tow weight doesn't exceed the tow vehicle capacity and the trailer capacity is not exceeded. Remember that you have to add the weight of the trailer to your overall weight. The trailer could be anywhere from 1800# to 2200# depending on the make and rating. Rims sizes are usually a good indicator of axle rating: 5 hole rims=3500# axles, 6 hole= 5200 and 8 hole= 6000 or more. Also have to look at the tires and see what load rating they are good for and not exceed the total combined weight rating for all 4 tires.