It is fine. (It's our backyard...) US 160 is a major east-west highway. There are two passes between Walsenburg and Durango plus a couple of good-sized hill climbs. In every case, there is a climbing lane. (Be forewarned that the downhill traffic is allowed to use the uphill's passing lane where there is visibility -- they will have a broken line on their side, so make sure you can see if you need to pass and don't cruise in the passing lane.) The longest uphill is only about 8 miles long in its steepest section. If we are roaming around here, we don't connect our toad, but that's just us. You should be fine towing.