TOW info should be in your owners manual. I think the sienna is rated at 3500lb. You could install a hitch yourself or go to a place like U-haul. Hitches are maybe $200-300 plus install (wiring). Reese, Draw-tite are popular brands.
Given that the 3500# rating INCLUDES you, your wife, kids, gear etc! - so assuming you, wife, kids, gear etc is 700lb (dogs, coolers, bikes, camping gear, canoe, etc) you would max out around 2800lb
I would get as "light" a trailer as possible. Be sure you are looking at the "wet" trailer weight.. ie, including any "extras" or even little things like "gallons of fresh water" "grey water" etc as these will also count against you.
Some folks like to upgrade/add "air bags" to the rear suspension to prevent sagging under loads. Wieght distribution hitches can also be used.
2005 LE AWD
Last edited by racerd; 07-19-2010 at 08:28 PM.