I am not familiar with the Dodge system yet; however, most cars and trucks have a resistor that is mounted close to the blower motor/blower duct. These can go bad and cause erratic blower motor speed.
Dave D
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2001. 5 QC, LB, 4x4, Auto, 3. 54, Everything but Leather, Bright Silver Metallic, ARE K Series, Diprocal EGT, Boost and transmission Temp in an Autometer Dash Pod, Westin CPS Platinum Step Bars - Black on Stainless
Dave D
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2001. 5 QC, LB, 4x4, Auto, 3. 54, Everything but Leather, Bright Silver Metallic, ARE K Series, Diprocal EGT, Boost and transmission Temp in an Autometer Dash Pod, Westin CPS Platinum Step Bars - Black on Stainless