Symptom of a bad strut bearing?

[SWDNJ@xxxxxxx]

During the past 2 weeks my 97 M3 with bilsteins and H&Rs  developed a VERY 
hard pounding ride on the front drivers side. At first i thought the strut 
blew and it was bottoming out... but no sign of a leak.  After paying more 
attention to the harsh ride, i began to realize it feels more like its not 
compressing at all instead of bottoming...
The only time i hear a slight rattling noise coming from the stut is when I 
begin to drive up my driveway at an angle. It must cause it to shift around a 
little bit.
Can the upper strut bearing  have gone bad it it was installed using an air 
gun?  thats what i heard.... Mine might have been put on with one when i had 
the suspention put on 15k miles ago.
If i do need a new one,  should i have both replaced?  with stock M3 ones or 
aftermarket?  and how much do they run?

Please email me directly with any suggestions, i dont know where to begin and 
dont want to get ripped off on labor trying to fix something that isnt broken.

thanks so much in advance,
Steve Dudash

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