Highway 77 in Arizona - recommended for a 39' motorhome?

But .. if all the talk about the Salt River Canyon bit makes you uncomfortable here is an easier alternative:
just south of Holbrook (77) take 377 SW to 277/Heber City and 260 into Patson. Then 87 south toward Phoenix. Watch for the junction of the "Bush" highway toward Saguaro lake. Past the lake, at the first stop sign turn left - Usurty Pass road becomes Ellsworth. Continue south to US 60. Take that east to Gold Canyon Rv park. Enjoy your stay!! becomes