Yes, as I remember, there is a long downgrade going south on 89 out of Page. After that, the rest of your trip to Grand Canyon Village will be pretty much non-eventful. 160 to Flagstaff is also a nice ride, as is I-40 eastbound.
You alone must make the decision to add many miles to your trip in order to avoid the 89 grade from Page south.
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BlueOx Towing Pkg, SMI Stay-n-Play
49 States & 7 Provinces visited in MH | WIT W112365