Co worker toured the Rockies a couple of years ago. Has a Dodge 3500 quad cab long bed dully with a 30 ft Avion travel trailer. He was working his way south to Durango from Gunnison Reservoir and Montrose and was just north of Ridgeway when he blew a trailer tire. After changing it, he elected to take the long way, via state rt 62/145/141 US 491/160 to Durango, rather than risk a flat on that stretch of highway south of Ouray.
If you want to "drive" it go to Google maps and select street view and cruise down it.
He got a new Carlisle Radial Trail HD installed in Durango (tire came highly recommended by the Discount Tire Store as being trouble free despite Carslile's bad reputation) When he got home he later inspected the three remaining Goodyears (all about three years old) and found knots or blisters on two of them, so they all got changed out for matching Carslile Radial Trail HD's.
He had already driven up Mt Evans and his wife was scared to death, so there was no sense pushing thing by taking 550 to Durango.
Charles