Hey!

I bought my car on lowering springs, but got my hands on some stock ones (needed for getting the car street-legal). After installing the stock ones, there is creaking from my car when I go over bumps or hills at slower speeds. The sound comes from the rear suspension, more specifically it sounds like it's from the actual springs.
Everything was tourqed to spec, springs mounted the correct way etc. All the bushings looks fine. The car never made any noise when it was on the lowering springs.

Any one got any idea what may be the cause?

 

Springs themselves won’t make noise, but step one is going back and double-checking everything you did while changing the springs.

 

You might pick up a can of spray lithium grease, hit anything that moves.

 

I guess that would be a good idea, I'm going to try this out. Thanks!

 

If rust is a concern you could also try Liquid Wrench. Don't use PB Blaster, IIRC that one is solvents only with no oil. Pretty sure the grease is kinder to the rubber bushings.

 

Check bushings.