This also might be one of the rubber "donut" couplings in the drivetrain. If these let go you will get that thumping sound as the driveshaft will not remained centered. Check them all..

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Jeff Lawrence
1989 300e
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.