The Law
Some (most?) states and provinces require trailer brakes. If you don't have trailer brakes, and have an accident (in a state where the brakes are required), you could be fined, sued, or both. And it won't matter whether the accident was your fault or not. The argument is that if your trailer is illegal, you should not have been on the road. If you were not on the road, the accident would not occur. You can't win, even if the other person was driving an unlicensed vehicle, or driving while prohibited.Re: sway. Check the tire pressure. Uneven tire pressure can cause sway. Check tongue weight. Tongue weight should be around 10% of your trailer weight (up to 500 pounds max, I think).Lots of smaller vehicles can pull a large boat/trailer, but the wear and tear will quickly age the vehicle. And you will void your warranty if you tow a heavier load than the vehicle is rated to tow.The rated tow weight (GCWR, or Gross Combined Weight Rating) includes vehicle weight, passengers, baggage, trailer, etc. In other words, everything! Lots of people make the mistake that because the dealer or salesman said the vehicle could tow 5000 pounds, that you can tow the 5000 pound boat, plus the kids, plus baggage, plus anchors, water, fuel, outboard, picnic tables, dinghy, canoe, kitchen sink, etc., etc., etc.