2007 RRS SC towing a 4,500+ lb boat and dual axle trailer over mountain pass. Beautiful job! Suspension ensured no sag. Unevenness over mountain pass was no problem. Power was fine as I was able to maintain 70 over entire pass. Previously had Jeep Grand Cherokee that did a fine job but sagged and didn't handle as well. RRS SC was a pleasure to pull a large heavy boat.