Re: 2004 highlander for a TV
Starting in 2008, the Highlander got a bit larger and the towing capacity increased to 5000 lbs. If I remember correctly, the milage stayed about the same due to the new VVT-i technology engine.
If you don't plan to drive this vehicle forever, and I doubt that you will, I recommend that you get the 19' if that's what you want and replace your tow vehicle a little earlier than you otherwise planned to. Tow vehicles come and go but a fibreglass trailer will be with you for a very long time.
2011 Escape 19