Hi
I have similar issue with Eibach pro springs. Got them installed last week (7 days now) I get very minor squeaking noise from front passenger side. I can describe noise more like spring squeak. Its very minor and can be noticed when radio off. If driven over big pat holes its fine but when driving slowly over uneven roads its there. Driving me crazy. I am not sure if it was there before as I started paying attention after spring replacement.
Also when car parked up, if I rock it, it can be heard depends what position its parked. E.x it can be always heard on my drive, its more quite at work car park. Today car was jacked up (both rear wheels) for pads replacement, and doest matter how much I rock it, no noise.
Took car to few different tyre and suspension places and all telling me nothing wrong, all seems to be tight as suppose to be.
I am very concerned as I will be taking car on 3000 mile road trip.