got my 300 4 months ago. been great. however, at first when slowing to stop, i would feel a wiggle in the seat of my pants. every indication telss me something in the rear end area. visual inspection soon followed and did not find anything that poked you in the eye.
it seems to come and go. recently it has been gone more than here. is it possible that the motor mounts may be worn or loose? i"am thinking that mybe the compression during decel may contribute.
any ideas?

That is pretty vague....
but you should have someone put it up on a lift and check the rubber bushings in your rear suspension... a pretty complicated setup..... compared to older cheaper cars... little things can really show up in the feel of the car.

the bitterness of poor quality , lingers longer than the sweetness of low cost.

Maybe sway bar bushings? or end links? Just an idea.

Or maybe you stared too long at that gal who had a little jiggle in the trunk!

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Sam

84 300SD 350K+ miles ( Blue Belle )

I had a wiggle similar to that and it turned out to be the center support on the driveshaft was completely shot and would cause the driveshaft to wiggle under certain circumstances...The support had absolutely no connection whatsoever to the center support bearing at all....Easy to check...Put the car on a lift and move the driveshaft up and down in the center....

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83 300CDTurbo 307,000
2005 Honda Element 266,000
56 Nash Ambassador Country Club Special 34,000(under restoration presently)

http://www.peachparts.com/shopforum/showthread.php?t=125099

Something that is out of balance is causing the wiggle. Check for either a out of balance tire or a bent rim. A bad mount or worn sway bar bushings in themselves should not cause the wobble. These will magnify the wobble but something has to be out of balance to cause the wobble.