What is this rattling noise from my suspension?

[Tyler]

I know it's nearly impossible to diagnose sounds over the web, yet here I am attempting to get some answers.

My wrx has this fast rattling sound in certain conditions. If I'm at speed, rounding a very mild corner to the right, the sound comes from the rear passenger side. Every little crack, notch, or rock in the road it seems, will make the noise in these conditions. If I straighten the wheel it'll usually stop. If I take a more sharp corner, I don't hear it either. It only seems to be when there is a slight amount of weight taken off that wheel. This is the only place the sound appears to be coming from.

In an attempt to fix this, I've replaced the endlinks which had bad bushings. This seemed to quiet it down a little, but definitely didn't cure it. Even more recently, I replaced the struts with some lightly used stock wrx struts and brand new groupN tophats. I was planning to replace the springs also, but there was a problem with the springs I purchased from a member several years ago. I ended up reusing my springs, as Evergreen assured me they were fine.

The tech at Evergreen was able to hear the noise, but was unable to make any diagnosis. He recommended driving with the swaybar unattached to determine if the sound was coming from there. I haven't done this yet as I haven't had time. I want to get some other suggestions so I can possibly cover more while I'm down there.

Does anyone have any ideas as to what could be causing this?

 

[2point5RS_Dan]

Pull the sway endlinks and see if its the swaybar setup.

Have you ever jacked the car up by the rear subframe front mounts? they're triangular plates with three bolts. If you jack from those it'll bend them and make a metal on metal sound.

 

[Tyler]

I don't think so, but I guess I'd have to look to be sure where you're speaking of.

 

[drvsdwz]

Check the rear sway bar mounting bushings, those could also be worn out, not just your endlinks. If you disconnect your endlinks, see if you get a lot of play with the sway bar when it hangs. That could be your problem.

 

[Tyler]

Good call, I'll check that out while I'm at it as well! Thanks

 

[inski]

You know where your rear diff mustache bar goes way out board towards the rocker panels. Check that mount (just inboard of the rockers underneath rear door) and make sure that under plate isn't mashed up into that huge bushing and mustache bar.