AStravelers said:I second the above suggested route. On I-25 north of Raton you have a pretty steep climb Raton pass and then a pretty steep drop down the north side. On the way up keep your RPM's up by manually shifting down to 4th or 3rd gear. On the way down manually gear down to 3rd or even 2nd to let the engine braking keep your speed down to 35-40mph or even slower. DON'T ride your brakes. Press hard to slow down 10-15mph in 10-15 seconds and then let the speed slowly build up for 60-90 seconds before braking again.
On US-50 west of Salida, you have to go over Monarch Pass. A long about 7% grade up and about the same down the western side. Again, gear down and RPM's up going up hill to keep your transmission from overheating and then on the way down gear down and stay off your brakes on the way down. You will have had some good experience earlier on Raton Pass.
By the way, "Raton" is pronounced ra-Tone
US-50 is a pretty drive.
US-550 from Durango to Ouray is a good road, but only for drivers of RV well experienced in driving on steep mountain roads.