Rt 89A Flagstaff to Sedona

According to the 'Mountain Directory for Truckers and RVers' there is a sign "Trucker's notice--US 89A not recommended for heavy trucks". "Southbound you will have 7% grade downhill for 3 miles, many curves including several 15 mph hairpin turns. The road is also very narrow. It has an additional 5&6% sections, narrow and winding." I don't believe there are actual restrictions.

Here's a YouTube driving it. You decide. :)

https://www.youtube.com/watch?v=1RKWqar-QWs