If your boat trailer is going to spend the off-season outside exposed to the elements, Boat Owners Association of The United States has five tips to protect your investment and eliminate problems down the road: A little spray will do you: Spraying lubricants such as WD-40 on metal trailer roller assemblies, winch gears and electrical connections will keep moisture away and rust at bay. It's also best to take care of any rust spots now on the (galvanized) metal trailer frame: sand, prime and paint. (Trust us; this will be the last thing on your mind come springtime.) Don't park ...