We towed a fairly large popup with our Sienna and it did fine. Of course two factors involved: no frontal area to deal with and most towing was done in and around Florida where our highest point is only 345' above sea level. Minivans can be very good tow vehicles when towing within their capabilities. Our popup was about 3300 lbs and we averaged about 15.8 MPG towing. We traded that van at 254K miles having never had a serious repair and no transmission or engine issues. All that being said, I personally would not tow a full-height trailer with one unless it was super light like in the 2k weight range and I don't know if such a beast even exists.