Dodge Repair Questions? Ask a Mechanic for Answers ASAP
I believe something has gotten down into the hvac system so when you turn on the blower motor it is hitting the item than pushing it away until you turn it off. It is possible a small mouse has gotten his way up in there causing the concern. The other possibility is the blower motor bearing is getting worn out causing it to be out of balance until it gets up to operating speed. We will need to open up the hvac case and have a look.
I have loaded the steps on removal of the HVAC box. I really have seen a mouse cause this condition a few times. They squeeze there way in there and sometimes chew threw the system.