I made that same trip in reverse at the end of Jan 2016. I bought my 2000 LC in Boise, ID and drove it back to Dallas with my brother. I have driven 550 several times in the summer and thought it would be quite the adventure to drive it in winter. Just so happens the closer we got to Ouray the more the weather deteriorated. There were DOT signs everywhere stating snow chains or tires, 4x4, and alternate traction device required. Oddly enough we never saw a cop, trooper, of BLM vehicle on the road. We seriously considered turning around for an alternate route once we made it to the Ouray overlook because weather was getting worse as we looked up the canyon. There was snow on the ground in Ouray but we didn't encounter heavy snowfall until half way to the summit. At the worst of it we had about 4" of fresh snow on the road and visibility less than 1/4 mile. As vehicles passed us traveling in the northbound lane it would take 1-2 miles before their tracks were covered in fresh snow. We drove slow the whole time, and performed numerous "brake checks" at low speeds on strait sections of road to get a better idea of conditions. The cruiser had Yokahama Geolander all terrain tires, with next to no load in it. We has ZERO issues. Truck performed great. I could get it to kick the rear out if I tried, but as far as mature safe driving it never gave me a reason to doubt. Once we hit the summit and started down the south side the storm blew out and the views were incredible. I believe the whole trip from Ouray to Durango took just over 3 hours(?). We encountered several vehicles along the way to Silverton and Durango that looks like they had no business being out on the road but seemed to manage. I believe a trip like you're considering in winter weather falls back to the, "its not what you drive, but how you drive it." You could make the trip in a lesser vehicle (Jeep, Land Rover, Nissan, Ford, GM, Dodge....

) just stay focused on the road. If you're going thru Dallas on your way up I have a set of snow chains your welcome to borrow. Just drop them off on your way home.
I managed to dig up some pictures we snapped along the way.
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