Suspension Noise at 100k, What to Look For?
 

Hi Everyone,

I will have my 986 up on stands this weekend for an oil change, and I would like to inspect my suspension for wear. For the last 1-2 years I have been experiencing some creaking when I go over bumps. It seems to be worse when it is warm outside, which makes me think it may be something rubber, a bushing perhaps? It is intermittent, and not reproducible by shaking the car when it is parked. I have never done any suspension work on the car, and after 100k miles I am sure something needs to be replaced. I had one mechanic I trust take a look, and he said everything was fine, but he doesn't normally work on Porsches.

I don't know anything about suspension, so if anyone could provide some pointers on what to look for/inspect with idiot-proof details/instructions, it would be greatly appreciated!

Thanks! :cheers:

If you can get it up on jack stands or a lift, grab each tire top and bottom and give it a good shake. Should be no movement. Repeat with hands at 3 and 9 o'clock. Take a good size rubber mallet and start whacking your suspension arms, listening for rattles and looking for movement. This technique tends to find only grossly worn items.

Most of my rattle issues, which were similar to yours, came from the metal shielding between the 2nd cat and the header flange. Don't think you have a second cat but give the exhaust system a tentative whack starting with the headers and moving onto the mufflers.

The easy part is to inspect all the visible rubber for cracking or missing pieces. After that it gets a lot harder. I just replaced my rear trailing arms and you couldn't see any problem with them, even after removing them. The ball joint seems tight. But when driving the ball joints would rattle every time I went over a big bump.

It also takes a lot of effort to shake the suspension because its so stiff.

drop links are notorious for rattling when they're old. They're not too difficult to replace and don't require special tools.

The creaking noise is typically caused by the lower control arm, coffin arm. The easy fix is to make a very small hole in the lower control arm ball joint rubber cover. Then inject either WD-40, grease or silicone into their, depending on your choice. The Fixx can last for a week or months, but it's not permanent. And by the way, the creek does not mean that the ball joint is bad period

But I agree with the sentiments of those above, you should shake down the entire suspension once you have it up in the air.

Thanks for the tips! I am planning to inspect everything as thoroughly as possible (including a thorough shakedown), I would like to finally figure out what is causing the noise, and check for general wear. It seems like the central wishbone bushing is a common issue, I will also look at the drop links closely.

Right now I am researching to get an idea of all the components and various potential points of failure. The main issue is all of the various nicknames for the parts, the Porsche parts diagram lists several things as just 'control arm' then I have seen Caster Control Arm, Wishbone, Coffin Arm, Track Rod, Toe Control Arm, etc.

I did just find this interactive diagram, which I think is going to be really useful. The only think not labeled are the rear trailing arms.
Elephant Racing | Suspension Navigator | Porsche Boxster/Cayman

Generally, the wishbone control arm will not creak. However, the bushing that attaches the wishbone to the frame tends to get a little loose and will make a the classic rattling sound over very small bumps at low speeds that most boxster owners complain of.

It's the LCA creaking. Most of the time you won't be able to reproduce any noises by shaking the suspension yourself, because you can't duplicate the forces put on the parts by the weight of the car and going over bumps can. My car was making every noise in the book (bumping, creaking, groaning and squeaking). It had 145K on it, and everything was original and shot. BTW, raising the car and shaking things was a waste of time, since it wouldn't make any of those noises for me.

Rebuilding the entire suspension took care of all the noises.

How many miles on your car? If it's over 80K it's probably due for new LCAs, not to mention drop links and trailing arms. At that point, since you have to have it all apart, you may as well replace the shocks and all the other bushings as well.

Welcome to Porsche ownership! :rolleyes:

Yes but actually, on any car with over 80k you will need to replace the worn suspension components you are mentioning.

It is amazing the difference on the car that a new set of control arms, struts, bushings, etc., does for it, and it will be expensive, regardless of the brand.

However, 80k miles are many years of service and fun..

Replace all your control arms. Oh..only if you have updated your struts.

Rick our cars are similar, mine is 98 w/98k and west coast driven. I recently changed the struts, Rears were in surprisingly good shape, 1 bad front, it had lost it's precharge but was not visibly leaking. With everything disassembled I inspected the lower control arms and they are still fine. I had replaced the rear upper control arms previously. The drop links were all shot and replaced at 78k. I upgraded the sway bars and replaced the bushings at 85k. At 100k I think you will need similar. As an FIO the struts are the most expensive and require the most disassembly, labor and tools. All other parts even the LCAs are bolt on and can be changed easily at a later date but an alignment will be required.

I've done this on my car as a 'nothing to lose' situation. Been a couple of years and no noise since. I think I shot a little lithium grease in the boot instead of WD40 but either way will at least allow you to troubleshoot the source of the noise.

For those of you who replaced suspension parts - is it generally a given that you should do an overall refresh of all the components at ~100k miles, or do you bring it into a shop and have them look at what needs to get replaced and only replace those parts? Might just be easier to replace all the parts given the suspension is coming apart anyway?

My thought was to replace everything while I had it apart, rather than going back to go through the same process later.

I had the same issues with my '00 S with 94,000 miles. I started with my repair shop taking a look and giving advice. They did a drop link and a coffin arm replacement with no change. I took it upon myself to change out every drop link, sway bar bushing, coffin arm, trailing arm, etc. and after a good re-alignment almost everything sounded and felt better. I also did a full shock/strut replacement this year and all those noises are gone. I'd say with your mileage it's time for a full refresh on these parts. I was surprised that none of the rubber bushings looked dried and cracked until I put them next to the new parts. They had all compressed and shrunk from the years of use which left everything to rattle.