Strut Mount or Strut Assembly?

I've been having this loose rattling noise coming from my front passenger's side wheel for a while now. You can hear/notice it the most when going anywhere from 1mph~46mph. I've already replaced the axle, wheel bearing, tie rod, and brakes/rotters. You can hear/feel a popping noise when the car is parked, hood up, and you bounce the passengers side down and up with your hand over the strut. You can actually feel the vibration of the pop with your hand over the passenger's side strut/mount. Obviously this is not normal and you cannot feel nor hear that on the driver's side. I was just wanting to know if anyone thought it sounded like a bad strut altogether or just a bad strut mount?? I should mention it doesn't seem to ride strange or anything, but you can just hear it. Your comments would be appreciated. Thanks.

Ok, say I do replace the strut or strut mount on the passenger's side. Do I absolutely need to replace the driver's side as well if it's not making any popping/rattling noise? I realize it would probably be good to have two new same caliber sturts/mounts but would you be able to notice much difference if you only replaced one or would you just probably have to replace the one that's you didn't this time around a little while down the road? Hopefully that made some sense. Thanks for any help anyone is able to provide.

I am having the same problem. The noise coming from my rear wheels could be decribed as a popping when you go over any irregularities in the road. Pretty annoying sound. Assuming I need struts as there are 140,000 on the car and not sure if they have ever been replaced. Question is, how do I know if I need the mounts also? I recently replaced the front struts and bearings. Have a pretty consistant noise coming from the front end too over bumps but it is a different sound.

I personally would replace both struts as a pair. You can replace just one, but to me that doesnt make much sense. Also I would order strut mounts online. The ones at advanced auto are $40 each.