See also:

Control Setting Suggestions for Various Weather Conditions
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To Resume Speed
To resume a previously set speed, push the RES (+) button and release. Resume can be used at any speed above 20 mph (32 km/h). ...

Overloading
The load carrying components (axle, springs, tires, wheels, etc.) of your vehicle will provide satisfactory service as long as you do not exceed the GVWR and the front and rear GAWR. The best w ...