I recently towed my 31' Travel Trailer (~8400 LBS) back and forth between New Brunswick, Canada and Florida. It was quite a trip, 3800 MI Round Trip. The truck worked great, rolling at 60-65 MPH. Anything more than that got a little scary with swaying. Averaged around 12.7MPG. Used cruise mostly in the lower states. Wondering if this is good/bad/ugly?