'08 Prix rear strut rattling noise

[guitarfish]

Hey guys,

I've been hearing this metal on metal rattling sound every time I hit a bump and it's been driving me insane. Finally tonight I pulled the rear seatback down, had someone sit in the back seat and listen.

They put their hand on the rubber cover of the strut and pressed down. Everytime I hit a bump in the road, they felt the strut moving up and down, exactly when the noise occurred. Passenger side only, btw.

Well, I pulled the cover off, and all the bolts seem to be nice & tight. I'm stumped. Any ideas?

Thanks!

[grandprixgtx00]

arnt you still covered under the 3 year 35K mile warrenty? probably a bad strut mount. couldnt imagine the strut being bad already

edit: nvm...just read your sig, you got 57K on it

[guitarfish]

Yeah, I'm actually up to 64K now. It's 55 miles to work.

So, a strut mount? I guess there's not much else there that it could be.

[tblake]

Yeah, I would have to agree, it seems like a bad strut mount.

Better take it back to the body shop since dropping the cradle probably shifted the center of gravity and put too much stress on the back strut mounts. Its defenatly their fault.

[guitarfish]

Yeah, I was waiting for someone to blame the cradle! I guess I'll never live that one down. :sarcasm1:

[tblake]

No, but seriously, if the suspension on 08's is the same as 97-03's, you can easily remove the strut yourself.

What I usually do istake the struts out myself, then when it comes to compressing a spring, I usually take it to the local auto shop which in turn compresses the springs (plural for both sides), replaces the bad parts, and puts them back together. It only costs 20.00 at my shop for them to do it. Then I come home and put the struts back into the car. Its WAY easier and safer this way that for me to be wrenching down a small little spring compressor from auto-zone.

[guitarfish]

Well I'm glad you mentioned that, because I've already started thinking about doing this. The only concern I have is what's involved in removing the strut down by the wheel. I had a 94 Prix, and watched a guy at Midas struggle for an hour with an air hammer trying to pop the bolts out.

There's a shop across the street at work that will swap the parts for me if I bring them in.

[tblake]

Its a cinch. It only took about a half hour per side on my rust bucket, so your 08 should be a lot simpler. You'll probably want an alignment when your done though.

[guitarfish]

Hey, a follow up question - when I look up the strut mount, it's listed as "without bearing". I wouldn't think there'd be a bearing since it's a rear strut. True? I want to make sure I order everything I need before teardown.

[tblake]

Yes, there are no load bearing plates for the rear strut mounts. Unless newer GP's have 4 wheel steering.... (doubtfull, but I've never worked on one)

[2000gpgtx]

Quick crawl under and tug of the sway bar wouldn't hurt .. I've replaced a ton of end links on the W-bodies, including my own. Ball sockets develop some slop and in turn create a more metallic rattle than the typical 'dead thud' of the strut mounts.

[guitarfish]

Well I checked the underside of the car, there doesn't seem to be any play or noise down below on the bars.

Another question - when I have the strut spring compressed, can I remove the strut rod nut using a ratchet alone, or do I need an impact wrench? The last time I did a strut (1992?) I seem to remember the strut rod spinning when I tried to remove the nut.

[2000gpgtx]

Been a lil while since I've had one apart, but I believe if u have some coordination and the correct torx or allen bit for the strut rod, you can remove the nut with a wrech.

[tblake]

Bingo!

Except it will only work like that on the back mounts. The front ones you will need an adjustable box end wrench.

[guitarfish]

OK, here's the report. Let my start by saying this was not a fun day.

I decided to use Moog strut mounts instead of the GM ones, since the GM ones were shot after only a year and a half.

I took the driver side rear strut off the car, very slow going since I hadn't done it before. I used a heavy duty spring compressor set to tighten down the spring. It's a slow process. Got the old mount off, new one on, and started releasing the compressed spring. There's no mark or indicator to show where the mount should be lined up relative to the spring, so I just put it on the way the original one was.

First problem - when putting the strut back on the car, the mount plate wasn't lined up in the same position the old one was, but needed to rotate about 1/4". The result was that the part of the strut that attaches to the knuckle would not line up. I had to take the strut back off the car, compress the spring again, rotate the mount plate about 1/4", and try again. It still wasn't perfect, but at least it went on without too much trouble. Unlike a front wheel strut which has a bearing and freely rotates, the back doesn't rotate. What an unforgiving process. Finally got the driver side done - THREE HOURS.

Next the passenger side. Now, I again had the same dilemma of how to line up the mount plate. Again had to adjust it a second time, still not perfect, but I got that side all back together - TWO HOURS.

The car is all back together. I drove it around the block, but not over the main road bumps where I normally heard all the noise - that's later today. It could be that the new mounts will be enough to keep things quiet, I just don't know.

This wasn't an easy job. I'm not a mechanic to begin with, I'm a computer network administrator. This was a little beyond my realm. 5 hours later, I'm sore, but it's done.

The last kick in the butt is I can't for the life of me get the rubber covers back in, that are in the trunk above the strut tower, to cover the nut. Not a big deal, but I'd feel better if everything went back together a little easier. EDIT: I realize now that these should've been slipped into place before I complete tightened down the three mount plate nuts.

Oh well. Live and learn.

Thanks for your help everyone. Not sure if I'll try this one again on my own.