Rear suspension noise

[Porsche man]

Hi all. I have a 2000 Boxster S with 80k on the clock. The car has developed a noise in the rear that occurs on smooth surfaces, eg concrete and at reasonably low speed, and when I run over a small bumps, say a cat's eye (reflective marker). The noise can be described as a kind of dull rattle. Suspect it is a worn bush on the rear suspension. I don't want to replace all the suspension components at the one time when it may not be necessary. Question is where do I start, and what suspension component from the experience of others is likely to wear out first ?

[pjv]

Likely to be the rear lower control arms. Mine wore out at about 80k km. I don't remember cat's eyes being enough to cause the rattle, but going over speed humps would cause a loud rattle from the back, which at first I thought might have been the soft-top frame bouncing in the back. It cost a bit to have them replaced, but I have seen on this forum that low cost arms are available and the job appears to be suitable for a DIY. Hope that helps.

[jcb986]

Trailing arm. It's notorious for the rattle. Sounds like it's coming from behind the driver seat.

[woodsman]

Lower control arm - coffin shaped???
Trailing arm - the one running longitudinal FR to RR?

I've often read here that anti-roll bar links can cause a rattle...
Time to squeeze under her and wiggle and tug on stuff ? If you do this on a hoist with the suspension at full droop it will skew the results if not completely mask them. Check all mounting bolts with wrenches as well.

[Porsche man]

Thanks Guys for your posts. Gives me a few alternative parts to consider and check.
I notice that some of the non Porsche parts are considerably cheaper. Noted that lower control arms on Ebay are half the price of genuine Porsche parts.
Is there any non Porsche parts supplier that is reputable?
Can the trailing arm be re bushed or does one have to purchase a complete new arm?
Cheers

[dagdisco03]

The long trailing arm is the one most people seem to have the issue with. I also have a 2000 S but with 117K on the clock and I have the same rattle. I did buy the trailing arms but have not had a chance to install them yet. From what I've read I don't think you are going to find anything from trying to feel play in any of the parts by hand. I know in my case I don't see or feel anything move but it rattles me crazy over the small bumps like 5 mph into a parking garage always rattles and drives me nuts but realy do I hear anything at full road speed.

[RandallNeighbour]

Be careful buying cheaper parts off eBay. There's a bunch of inferior parts being sold by sellers like DeutchParts out of Germany that are just crap.

Vertex Auto has some really good aftermarket control arms (all three actually) with poly bushings that will last a long time, and they discount them heavily if you send back your old ones so they can rebuild them and sell them to the next guy.

I concur that it's probably your trailing arm bushing going out, but it might be a drop link as well (they're cheap and easy to replace).

[Porsche man]

Thanks Guys. Your posts have been a great help. Just the information I was after.
Vertex parts seem to be the way to go Prices seem to be on the right side even allowing
return freight from Australia.
Thanks again for your help.
Chas

[Giller]

Hey - I have this same thing, sounds like marbles rolling around back there at really low speeds. Been told my rear control arm has 1/64th play....how serious is this as an issue to get fixed? The noise is annoying...but is it something that needs done today or tomorrow or okay to wait some time? I'm not doing the fix myself - and have heard the repair is extremely expensive for this??