Then, if you have the time, definitely hit Sedona. Crown King, the back road, can be difficult for an unlocked and stock 4x4 especially if wet. But it is an entertaining ride with great views and some nostalgia to boot. Supposedly the Viking from "Gold Rush" has a claim up there. I can't confirm it.
Sedona: Broken Arrow:
JeepTrailInfo.com :: Broken Arrow Trail
Sedona: Schnebly Hill Road:
JeepTrailInfo.com :: Schnebly Hill Road
Sedona: Soldiers Pass
JeepTrailInfo.com :: Soldier Pass Trail
Alternately, you can take the Pink Jeep Tours through this area and not bother renting a 4x.
If you don't mind a "road trip". Out of Glendale head up to Wickenburg and then up to Prescott. From Prescott go up to Jerome (ghost town) and through the Verde Valley to Sedona. From Sedona, you can then head up Oak Creek Canyon to Flagstaff and see the sights around there or head back down I-17 from Flag to Phoenix. Or you The trip from Glendale to Sedona can be done in 4 hours but, you will be stopping and taking in the sites along the way. In reality, it is a day trip. The scenery from Wickenburg to Sedona (and Oak Creek) is fantastic, a must see and is all paved. Combine this with the off-road areas in Sedona and I promise you, you will not be sorry for taking it!