I just put on some Prodrive springs on my '03 WRX two weeks ago. They're great and the car seems fine, but every once in a while when I go over a bump (usually turning right into a driveway or parking lot off the street) I hear a "cha-chunk" coming from behind the right rear passenger seat (where the spring is).

Any idea what it could be? Thanks.

The springs probably were not seated right, or the top mount was not pushed all the way in.

Thanks. Hmm... so I should probably get this fixed before I get my alignment done, right?

Yep.

the top mount nut might not be tight enough and there's play on the top mount/spring.

Is this the top mount nut?
If so, can I just tighten it as it, or do I need to take everything apart
and tighten it that way? I ask becuase I have the same situation as Bosk.

Yeah, just make sure every nut there is tight. My problem was that the spring wasn't seated right... so it had to be taken out and reseated.

Now I'm having a different noise with my left rear spring, although I know what that problem is... one of the bolts (like one of the three long ones above) back there actually broke off when I was trying to loosen the nut when putting on my new springs, so what's left of the broken bolt is rattluing around... I think I'm going to try to put the broken part of the bolt back on with some of the liguid steel stuff that is suppossed to bond metal...

Bosk,

REPLACE THE TOP MOUNT!

You cannot weld metal without a welder, and welding the stud back together is a bad idea anyway. There is a torque spec for those fasteners and it's rather low. Make sure you know all the torque specs before doing work on your car.

Interesting, the guy who helped me install the springs (a mechanic who worked on Subarus) said he's seen worse and that I'd be ok without the one bolt. It actually has been ok for about a month, and only stated making noise this week.

As far as the bolt that broke when we were doing the install, it was on really tight, and in trying to get it off, it just broke. It was wierd b/c the other ones came off so easy.

Origami posted by Bosk
Interesting, the guy who helped me install the springs (a mechanic who worked on Subarus) said he's seen worse and that I'd be ok without the one bolt.
That guy's statement is one of the stupidest things I've ever seen in print. Subaru put three fasteners there for a reason. Omitting one of the fasteners spreads the load unevenly between the two remaining fasteners, possibly leading to complete failure of both of them someday.

If you are unable to do the install yourself, I would suggest taking your car to a shop like Gruppe-S.

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