Driving at 65 the other day I lost the dust cover that goes on the driveline just in front of the center carrier bearing. When it ripped off I thought I was losing the driveline from the noise....

My question is this:
What would cause it to rip loose? it split into three pieces (of which I found 2) and besides hitting something in the road that may have bounced up and hit it is there another cause for this happening? I did not hear anything hit the underside of the car but maybe that is all that happened.

Thanks for the input...

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'99 S420 - Mommies
'72 280SE 4.5 - looking to breathe life into it
'84 300SD Grey - Sold
'85 300SD Silver - Sold
'78 Ski Nautique