Need help diagnosing suspension clunk and steering wobble
 

Hi all, this is my first post in the group. i usually just read others posts but this time i have not been able to find anything relating to my problem on any of the forums.
I have a 2000 2.7L boxster 986 and for awhile i have had a dull clunk only on occasion from the front drivers side wheel area. However over the last month or so it has been getting worse and worse. it clunks over any bump or even if the asphalt is slightly irregular if i hit it a certain way. it may not do it over bigger bumps if i go slowly.
from what I have read a clunk could be anything like a strut or strut bearing, wishbone, control arm, tie rod ends, wheel bearing etc.

however now that the clunk has got worse im realizing that it is effecting the steering of the car. when i go over bumps the car steering wheel shakes back and forth a bit and i have to fight it a little. and on the highway the steering also slightly vibrates and every time i hit a bump with the driver side wheel it clunk and the steering shakes. If i hit a bump with the passenger side front wheel the car is fine.

Ive jacked up the car and given it a good shake down and found that when i turn the steering wheel, both wheels move the same amount and when i move the wheels the steering turns the same amount. no clunks. so i dont believe its a tie rod or steering issue. also the car turns fine on the road. it just gets squirlley when i hit a bump.

I've been trying to inspect the wishbone and control arm and drop links but don't find any cracks or tears in the boots/bushings. and i cannot find any play with the suspension loaded or unloaded. but maybe im not doing right?

I've inspected the upper strut mounts and they seem to be good and bushing is still there, maybe half inch of solid bushing.

I also shook the wheel at 12 and 6 and found no play so im assuming the wheel bearing is fine. there is also no road noise when just driving along. only when i hit a bump and only when i hit a bump a certain way.

Also; when i jump up and down in the trunk or push on the fender side to side or up and down i cant get any noise at all because of this im leaning more towards the tuning fork/control arm. track arm or whatever it is called forward most control arm.

any help would be really appreciated! Im leaning towards the ball joint on the wishbone or the ball joint on the control arm but not sure which would cause this issue.

What's your mileage on the car? The answer is likely going to be a lot of things. I'd start with the easy stuff. Tie rod ends, drop links. Probably control arms as well. The truth is that these cars have suspensions that are pretty much worn out by 90-100k miles.

my car has 230xxxkms so about 140xxxmiles

Based on what other boxster owners have reported, the spherical bearings in the rear track arms are pretty notorious for making clunking noises when hitting a bump at the rear wheel, after they get sufficiently large miles on them. Because I don't see why a similar problem couldnt happen at the front suspension (the front boxster suspension is basically the same design as the rear, but just a little lighter duty), replacing the front track arm would be my first instinct as to what you might try to fix your clunking noise.

(Alternately, you could try repairing the spherical bearing using this "peening" procedure - but of course, on your front track arm instead of the rear:
http://www.renntech.org/forums/topic/20681-boxster-control-arm-repair/ )

IME, the rear track arm clunking noise won't happen if you are dragging the brakes or accelerating while you hit the bumps - so something else you could try to learn about your problem better would be to try dragging the brakes lightly while going over bumps that you'd expect to make the noise, and verify whether dragging the brakes prevented the noise from happening.

Strut mounts probably wouldn't care whether you we're dragging the brakes or not. Ball joint noise might be quieted if you varied the lateral force (e.g., cornering or driving on a banked surface), but could respond to brake dragging also. Track arm bearings might also make noise regardless of lateral force (although I haven't tried that test yet on my clunking rear, I might have to now!). Steering tie rod end noise should also not be particularly sensitive to dragging brakes, assuming your suspension is not too badly engineered or tampered with (scrub radius isn't too badly out of whack).

Edit: here's a YouTube video showing the front "track arm" replacement procedure:
https://m.youtube.com/watch?v=899_OjGjBMg

jakeru thank you very much for your reply. Yes its this front trailing arm that ive been suspecting as the culprit so i will probably end up replacing this first or maybe trying the repair that you posted (thank you again)

I will try dragging the brakes in the morning but i can tell you that the noise does happen if under acceleration over bumps and turning while accelerating also seems to still make the noise but i will try braking in the morning.

Called the local porsche dealer here and the trailing arm cost is $358 for 1 pretty pricey. so i might try the fix and see if i can hold out for an online one to ship in.

Thanks for the link to the video, Ive actually seen it earlier today in my searches and watched it a few times lol.

One thing im concerned about is if it could be the trailing arm bushing that sits in the wishbone and not the ball joint on the trailing arm. or are these not so prone to wear/noise?

Like I said, the bushings in the control arm look good with no splits and the boots on the ball joints have no tears but they are hard to inspect. still cant find any looseness

[QUOTE=Gordons986;486752]
Called the local porsche dealer here and the trailing arm cost is $358 for 1 pretty pricey. so i might try the fix and see if i can hold out for an online one to ship in.
/QUOTE]

Gordons, FCP sells the TRW trailing arm for a reasonable cost
https://www.fcpeuro.com/products/porsche-suspension-control-arm-98733104302

and also the Meyle brand (Germany) for even less.

https://www.fcpeuro.com/products/clone-porsche-suspension-control-arm-front-forward-911-boxster-cayman-por-99734104300

I had very good experiences with the support from FCP, good luck

My guess is that since you are getting some shaking of the steering wheel when you hit the bump, it's the tie rods or the ball joint on the control arm itself. The trailing arm will make the noise, but shouldn't cause the shaking that you described.

Jacking up the car and trying to wobble things around won't necessarily cause any noise or show play in the components, because you can't load the components as much as the weight of the car going over bumps can.

If it were me, I'd try the tie rod ends first, then the controls arms. My 2002 has 144,000 miles on it, and it clunks, squeaks, and bangs a lot (replacing the rear trailing arms helped quiet it down a lot; now you can have a conversation in the car without having to shout), but fortunately there is no shaking in the wheel. I'm going to replace all the suspension parts one of these weekends, which should take care of all the noises.

[QUOTE=Gilles;486798] The first one, the TRW, is for the back, and although it is the 987 part number it fits the Boxster, I just installed 2 of these.

The 2nd one, the Meyle, although it is listed as the front caster control arm for the newer boxsters, I don't think it is compatible with the 986 Boxster fronts. Meyle does make a part that fits our Boxsters, their part number is 416 050 0004, but it is just getting out there and is not widely available yet. Interestingly, they give 3 equivalent Porsche part numbers for it, matching 986 and also this part number: 997 331 043 01 which is the 997 Porsche rear link (996 used the same as our fronts in front and back, 997 uses the one linked above as the front and the 997 331 043 01 in the back). Since Meyle says it is the same, I wonder if we could use the 997 back TRW part on our fronts, which is still available?

Who wants to be the first to try it out :) Or read another way, who has the best return policy :)

Edit: Ok so today it is very wet and rainy here in Vancouver Canada and i took the car down to the local auto parts to buy oil etc (needs a change) I drove the whole way with radio off and listening to the noise except the noise happened for the first couple blocks but then got quieter and quieter.

I was also trying dragging the brakes over bumps that would make the noise and no sound. by the time i got home i pulled in and out of my driveway a few times trying to make the noise but it wouldn't.

So im wondering if water is getting into something to stop it from making such a bad noise acting as a sort of lubricant?

@Racerboy - the feeling of the wobble does feel like a loose inner tie rod but ive inspected the tie rod ends and there is no play so perhaps it is the lower ball joint on the wishbone as you describe?

If it was the lower ball joint would I be able to replicate the sound by getting me and another to push up and down on the fender? because Ive tried that also and nothing.

Leads me to believe the noise may be of longitudinal movement rather than lateral movement.

@stevedox - Not sure if ill try the 997 trailing arms but i thank you for the input and part numbers!

Any thoughts on why the noise wouldn't happen in the rain?

Gordon, I'm afraid that you are going to have to face he fact that your suspension is worn out @ 230,000km. Its going to be an expensive exercise no matter what you do - shocks, shock bearings, coffin arms, trailing / control arms, drop links, steering rods etc etc. Probably $3000 in parts if you do the work yourself, plus a 4 wheel alignment.

The rattles, clunking, squeaking and steering wobbles are being created not by one worn component, but a combination of wear in all the multilink bushes and ball joints. Pushing, pulling, tapping with rubber mallets while the suspension is either loaded or hanging makes not the slightest difference to detecting the wear - believe me, I spent 3 months chasing down a single worn control arm bush which knocked only over corrugations. I finished up replacing ALL of the front suspension @ only 75,000km.
You are entering the expensive end of owning an old, high mileage Porsche - replacing "ad hoc" only parts of the suspension is not going to fix your problems....

Steve, I know what you mean but i have owned the car for the last few years and do most of the maintenance myself and have had the car looked over by the dealer within the last year and have never encountered steering problems or suspension issues. This issue started out of no where so it is to my belief that the wobble and the knock are cause of the same part failing. I believe probably most parts are nearing their failure point as well. I have all receipts for the car since it left Porsche in 2000 and there are no records of anything being replaced short of the left rear wheel bearing.

While we are on the topic of replacing struts could you recommend a good site to buy new struts from? would i need new springs? or would you rather recommend coil overs? and could you refer me to a site for that?

I believe i will probably end up replacing the wishbone/coffin arms and control/trailing arms on the front first along with the swaybar links. and go from there.

I am looking to autoX the car in the new season coming up.

I'll be following this thread and learning as I go. I just ordered front and rear lower control arms (the "coffin arms" and tie rod ends (both inner and outer). I've already got new sway bar end links front and back, and bushings all around.

I know my left rear track arm is sloppy and now I'm suspecting the ones up front.

I got my Bilstein shocks (my back-ordered rears just got in yesterday!) from ECS Tuning, but they are currently having a sale on Koni's right now. If I had to do it over again, I'd get the Koni Sports, they may be what you are looking for if you will be autocrossing. Pelican prices are competitive, but it's worth comparing the different vendors. I got my shocks, trailing arms, and various bushings, bearings, and bump stops from ECS, but the control arms, drop links, and tie-rod ends I got from Pelican.

You probably don't need to, but I am also going to replace the springs because I want it to be just a bit stiffer. Since I don't want the car to be drastically lower, I went with Porsche M030 ROW (rest of world) springs, which are the sport springs from cars sold in non-American markets (slightly stiffer and lower than the American sport package springs). I got the fronts (I think) from ECS, and the rears from a Porsche dealer who discounts parts.

My left rear trailing (track) arm was very bad. The passenger side was also bad, but it wasn't nearly as noisy.

Depending on the type of bump, my car makes different kinds of noises. If I'm turning sharply into a parking lot over a sidewalk ramp, then my front balljoints squeak and I can feel a "clunk" where there is sudden lateral movement in the suspension. If I am driving at more normal speeds, then there is still a lot of clunking from the rear suspension, but it's much reduced with new trailing arms. The front also rattles and sometimes clunks in normal driving.

Despite what is clearly a worn-out suspension system, the car still drives really well, and doesn't wander or dart around. I'm excited to experience the car with all new parts; it will probably drive terrifically awesome! :dance:

In the front, acceleration wouldn't be expected to quiet the trailing arm spherical bearing noise, since the boxster is RWD not FWD. Only the rear suspension components could respond in a meaningful way to engine brake or engine acceleration (or the application of e-brakes, for that matter, since they are only hooked up to the rears.)

You can easily inspect that joint after you have the trailing arm disconnected. It's rubber. Look for any cracks or tears. If not cracked or torn, not sure you'll see any benefit from replacing it.

I may be wrong, but I wouldn't rule out the track arm joints potentially causing a steering issue. If the fore-aft movement is significant enough, it would affect caster, which would affect steering. I guess it's more of a hunch of mine because I also have a similar steering inconsistency, which seems caused by accel/braking. I recently rebuilt lots of suspension parts and refurbished all of the balljoints and tie rod ends (all of which seemed reasonably tight), but I'm pretty sure I have a noisy rear track arm spherical bearing, and suspect this also may be responsible for the slight brake/torque effect on steering that I'm still noticing even after changing out all the shocks and closely inspecting pretty much everything. (I just won't be 100% certain I've properly diagnosed my own problem here, until I repair the loose track arm joint and verify whether it actually solves the small steering inconsistency.)

I think you have some good info which suggests track arm joint as the likely culprit.

Either that or possibly helps keep the joint cooler, and the hot vs cold affects the joint looseness due to material expansion/contraction.

Thanks! I will definitly check out those suppliers. I will probably also opt for the M030 package as i do want a small amount lower and stiffer springs. mind you i do daily the car :rolleyes:

Glad to hear you are getting it all replaced and good luck!

Jakeru; yes i too think that a caster issue could cause that type of steering feed back. From what ive gained today the trailing arm is the likely culprit.

However today i checked powersteering flud and topped up (was about an ounce or 2 low) and did my engine oil change after the rain stopped here. when i was doing this I thought id take a fifth or sixth look at the suspension upfront with someone shaking down the wheels and steering wheel while i was under and also me prying on things. however i still cant find any looseness.
I talked to my family friend and porsche mechanic today and asked him about it and he said something with the feedback im describing and noise should be very obvious.
anyways... i put the car back down and drove in and out of my driveway a few times with someone standing outside listening and the car still wouldnt make the noise. took it around the block and still no. didnt get any wobble over bumps either but then again i only got up to 50km in the neighborhood. Ill take the car out again tomorrow for a good run and see if it makes the noise then (hopefully whether holds out) in the mean time i will start researching and probably ordering parts to redo the suspension:D

Not to be argumentative here, but the play in a track arm would be so small if they were really shot (less than 1 mm), that the effect on the caster would be miniscule. Go ahead and replace the track arms, because those are fairly easy, but I'm pretty certain that it is something else that is causing the shaking of the steering wheel.

Gordons986, I wouldn't get too excited about it being wet making the noise quiet down. There is no way your problem has magically disappeared, unfortunately.

Haha don't worry I'm not excited at all if i seemed that way. Just really curious as to how/why the the noise just wouldn't happen yesterday when it has never stopped and only gotten worse since it started. and i still cant find any tears or looseness in anything with the help of someone else and a mechanic. just strange and trying to give you guys all the details.

again the feedback through the steering isn't much but it is present. I got out earlier and opened the car up at bit and was able to hit some bumps going about 70-80km and still no sound but i am getting the play still.

when i hit the bigger bumps the whole car sort of shakes like a shiver and the wheel does the same, you can just feel something isnt right. and when i go over smaller bumps like tar strips i dont get much feedback unless im going over 100km but i do get the noise (or i was getting the noise) I have to go for about an hours drive here in a bit and ill see if i can get the noise again. its cleared up here again so see what happens

Okay so I took the car out for a drive for an hour and no noise but some pulling on the highway the whole way there. on the way back however i had noise and still a little pulling/feedback. I took a video on my way back and you can hear the noise that im talking about and the steering wheel shake im talking about/ pulling. Im just uploading it to youtube now and will post the link when its done (about 1 hour)

In the mean time i took some pictures of some of the suspension components in the offending front driver side wheel area for you guys to see. and i also took some of the rear end for you to see. and i believe its worth nothing that both sides front and back look identical. the first 2 pictures are of the rear suspension... Attachment 20136

Attachment 20137

this is a picture of the bottom of the wishbone on the front drivers side. the trailing arm bushing...

Attachment 20138

This is a picture of the strut on the same side... the bump stop is almost completely gone. however this is intact on the passenger side and rears.

Attachment 20139

and this is a picture of the trailing arm on the front drivers side at the ball joint connection.

Attachment 20140

more pictures of the front suspension...
this is a photo of the lower ball joint on the wishbone that connects to the carrier..
Attachment 20141
this is a photo of the outer tie rod end...
Attachment 20142
this is a photo of the stabilizer/end links
Attachment 20143
here is another photo of the lower ball joint on the wishbone
Attachment 20144

here is the link to a video i posted of the noise on youtube. you can hear the noise at about 4:20 during the video very clearly and a little steering wobble. there is another rattle from my wind deflector just so you know and try to ignore that. that on is obvious.

https://www.youtube.com/watch?v=sCjROtwLd80

Okay so in the meantime ive spent the last few hours looking at several site you guys have referred me to and made a chart so i can pick out the cheapest prices for the best products.
I also have to take into account american exchange rate; please inform me if one of the sites is non american and is euro or canadian.
First i called my local porsche dealer which of course was the highest prices i found. over 500 per coffin arm and over 300 per front trailing arm. i wont even get into the rest of the pricing.
I checked out suncoast, pelican, FCP and ECS tuning and found that each site got cheaper as i went in that order... for the same products (mostly TRW)

so i ended up at ECS tuning finding the coffin arms for $86 the front trailing arms for $129 drop links for $32 swaybar bushings for $32 koni shocks for $862 H&R coils for $300 new strut bearings $34 and strut mounts $34 and new bump stops for $10

Im considering dropping the money and ordering it all and doing it all at the same time my self. but im also considering just doing the drop links, coffin arms and front trailing/control arms to save some money until i can really decide what i want for new struts...

I know ill save myself an alignment if i do it all at the same time however...

what are your guys thoughts? and has anyone ever had any experience or heard anything about the stagg struts? I came across this brand as i was searching the internet for parts. they were listed on ebay.

I hadn't heard of FCP when I was shopping for my parts, so I ended up just going to Pelican and ECS. It turned out that Pelican was slightly more expensive, but in the end was cheaper once you factored in the free shipping (once you spent over a certain amount). Just something to think about.

If you are going to take it far enough apart to get the coffin arms out, you may as well do everything else at the same time. As you mentioned, you'll only need to get an alignment done once, too.

Be aware that the H & R springs will drop your car about 40 mm (1 1/2 inches). That is pretty low for daily driving in my opinion.

My local Firestone offered a "lifetime alignment" which applies to the vehicle as long as you keep owning it. Could be a good option for you to consider if you potentially see multiple suspension service jobs in your future.

I would stay away from any bargain brand (you can find on eBay, but also I seem to recall ECS sells one called "Hamburg technic", so specifically beware of that) on any rubber suspension components, (especially when you aren't sure that there's anything wrong with your current part - in which case your preventive maintenance could easily backfire and cause more problems than doing nothing).

IME with other bargain rubber parts (like aftermarket engine mounts purchased for other cars), they can look fine when you first get them, but self-destruct very shortly after installation.

I still personally believe your steering inconsistency could be caused by just a worn out trailing arm spherical bearing. My front bump stops on my '01 base with 110k were also obliterated before I did suspension service. If your suspension bottoms out frequently (mine did), replacing them will help improve that. Best to do bump stops at the same time as replacing the struts, though.

Trailing arms repair or replacement could easily be done as a standalone project. When you get to replacing struts, you have a much, much larger scope of project on your hands. Hope this helps and best of luck!

Do you know if the free shipping applies to canada? ive bought from them before but never over $100 so i dont know if that works but ill definitely check that out.

also yea i didnt know they would drop my car that much, where can i find the euro M030 ROW springs? or do they come in a set with struts? meaning i couldnt use the Konis?

Thanks! Im about 90% sure that it is one of the two ball joints/one of the two arms. so i think i will start with the trailing arm. is there a way to inspect the arm once its out? i wouldnt mind taking it out and inspecting it and putting it back if its really not in need of replacement. but i hear the TRW ones are a good upgrade.

definitly going to stick to TRW unless there is something that TRW dosent make then i will look for another reputable brand.

The other thing is that my suspension has only bottomed out a few times in potholes and pulling into some driveways with speed. when i push on the fender or jump in the trunk the suspension goes down and comes back up without ocilating. leading me to think the struts are good but may be in need of replacement. i am looking at doing autox events here want a slightly lower ride height but not too stiff because i do still daily the car

I'd just go ahead and replace the trailing arms, because with that many miles on them, I'm sure they are worn out. When I replaced my rears which were clunking badly, I looked at the old ones, and they looked and felt fine. But of course they were shot, since the new ones fixed the clunking noises.

Okay thanks for the help! ill order and replace the trailing arms and report back!

Good luck! BTW, you shouldn't need an alignment if you only replace the trailing arms.

yea this is the bonus! was just about to order the trailing arms from ECS but i found out while i was paying that they wont ship to PO boxes. I have a PO box in washington so i dont have to pay duty and still get free shipping. I emailed them and hoping they get back to me on monday

Any updates on this?

Noise at 4:20. I would say engine mount.

Wobbling steering wheel: Tyre balance?

Car tries to drive to the left: wheel alignment? Not even worn tyres?

Pictures: you need to check all control arms for play. You can't see from that picture if something is worn. ;)

Regards, Markus

Cliff Notes: Check the shock pinch bolt that the top of the drop links go through (63 fit lbs)

So I found this thread and a few others since march when I got my 2001 Boxster S with 58k miles . I had a some clunks and a wobble, wandering steering on bumps.



The very first service I did on the car was a oil change and a brake job - new pads and change fluid. Rotors looked on as far a thickness. Pretty much my standard items when getting a used car.

After a month or so I started to drive more with the top up and on the freeway and I noticed the clunks around town and the wobbly steering at speeds over 60 mph

The next item I replaced was inner and outer tie rods on both sides. This made almost no difference at all.

After a month or two of clunking over small bumps at low speed, I replaced was the front and rear track arms. New TRW units cost around $400 total from elephant racing (front) and summit racing (rear).

That pretty much solved the loud rhythmic clunks around town, but the wobbling steering and occasional random clunk when unloaded after a bump remained.

I had a rattling exhaust baffle, so I changed that out and wasn't sure if the clunking was related to new exhaust.

The next items I replaced were front sway bar bushings. I did a few adjustments to bring more toe-in on the front end alignment.

Random clunks remained around town 10- 20. Wobble/ unstable remained Especially over 60 on the freeway.

So I ordered new drop links all around, rear swaybar bushings and engine mount insert,.

I was beginning to think I would have to go all the way and replace coffin arms, shocks and rear toe links.

When I changed the droplinks on one side, there was no change.

A week later the parts for the other side and rear sway bushings came in.

This time I made sure that I torqued the top bolts on the sway bar drop links to 63 ft lbs and the bottom bolts to 37 ft lbs (~450 in lbs as my large torque wrench wouldn't fit).

I was "shocked" and how many turns I got on the top bolt after it was tight with a 15mm and a 17mm backup. When I finally got it to 63 ft lbs, I realized that the other side probably wasn't tight either.

I think this was the problem all along -- one stinkin' bolt not tight. Its the same bolt that pinches the bottom of the shock to the hub knuckle.

So for those reading this in the future:
1) check the pinch bolt for the bottom of the shock - torque it to 63 ft lbs
2) change the front and rear track control arms.

What a hassle this was to track down!

+1 to jedblanks

Thank you. I read your post this morning and went out and checked all the suspension points you discussed and, lo and behold, the right rear drop link attachment at the 'pinch point' required re-torqueing to the tune of 3/4 turn.

I had been experiencing a 'clunking' or 'rattling' noise over expansion joints while driving slowly and i was convinced was from the front. I had replaced the sway bar bushings front and rear and although the noise was less pronounced it was still there.

This solution of ensuring the proper torque on the various bolts has done the trick. I was very close to pulling the trigger and buying new drop links all around but now i can put that off until they do start to fail.

Again, thank you.