So recently I replaced all shocks and struts and drove on them for a month with no issues. Last weekend I decided to replace the sway bar bushings (MOOG) as well due to a clunk that I was hearing. I drove the Mazdaspeed 3 for a whole day with no issues. The very next morning I took it for a drive and now hear what sounds like a crunching noise when going over large bumps. I checked all the suspension components and even took it to an independent shop where they too could not find anything wrong with it. Thinking back I remembered that when we changed the bushings we had to remove 4 bolts that also hold part of the subframe together. We tightened them as much as possible and the shop even confirmed that several days later.

I am completely lost! It almost sounds like the frame is under stress. Could I have tightened the bushing brackets too much? Do they need grease?

Please Help!