flange- do you mean the hub on the wheel side? try tightening the bolt, accessible from the outside by removing the wheel center cover,or the wheel.

if it is the hub, you will have to replace it. see Dmorrison's post on rear wheel bearings.

if it is on the diff, ?maybe bearings there? if it is a can axle, replace the axle.

good luck,mo

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1984 123.193 372,xxx miles, room for Seven.

1999 Dodge Durango Cummins 4BTAA 47RE 5k lb 4x4 getting 25+mpgs, room for Seven.