I have a 2005 MCS with 55k on it and only 1500 miles on my new suspension (Koni yellows and H&R sports). Just this past week it has developed a chirping noise coming from the front drivers side corner over harsh bumps. It literally sounds like a bird is under my hood when the noise happens. On smooth roads and over normal undulations in the road it is perfectly quiet. Any ideas? I've read elsewhere that it might be the sway bar bushing on that side??

 

I actually have had that annoyance for the past month on the stock suspension, and i'm stumped to where its coming from on that side.

 

Its weird, the noise seems to be somewhat intermittent now. Its gone now but will probably be back later today for all I know.

 

Had a similar noise from passenger side but mine did it while turning. Turned out to be the yellow strut bumper was dry and rubbing on the shock shaft. Greased it up and it hasn't come back since. Without hearing your noise, I would say check sway bar bushings and/or strut bumpers.

 

I had some strange intermittent noises that sounded suspension related...turned out to be broken exhaust hanger tabs on the center pipe...they rusted off at the pipe