Steering vibration after spacer install?

Just installed 10 front 18 rear adaptec hub centric spacers (with the lip) on my oem turbo twists on brand new, balanced tires and I�m getting a steering wheel vibration that�s mostly noticeable above 60mph. I did some research and did the following: took off the spacers and scrubbed the grime/rust off my hubs, reinstalled and torqued the wheels to the hub while the car was on stands. I have extended lugs that came with the spacers. One thing I can note is the rear driver side hub seems to be slightly expanded, in that i had to apply some force to get the spacer on there, but I believe this vibration would be the result of something going on in the front. Control arm? Wheel hub? But wouldn�t I feel these things even without spacers? Any advice is appreciated!

If the spacer is seated fully and sitting flush on the hub, you shouldn't get any shimmy/vibration with the spacer (that you didn't have before). It's possible that due to the wider track, it's exacerbating some other weakness in your suspension - LCA's, wishbones, ball joints, tie rods etc...

Since you have OEM wheels and are using spacers, remove the spacers and see if you have the steering wheel vibration. New tires may not be balanced correctly.

18 mm seems excessive, are these on a nb 996?

Remove spacer and test the newly balanced tires out without them on the car. If spacers are super tight fitting on the hub or inside the wheel take a file or grinder to it until it is snug but not impossible to pull apart. I hope you went with extended lug bolts when you opted to use an 18mm spacer. Stock lugs with an 18mm spacer would most certainly be unsafe, and may even be causing your issue if they are not fully seating

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That's what I was thinking. Will removing them both and then introducing them one at a time help me narrow in on which side is causing the issue, or do things need to be balanced? Is there a way to zero in on the specific suspension part that may be causing this? I have had some minor suspension squeak from the front end when driving since I bought the car but did the "push down on the front end of the car" LCA test and can't get it to squeak, so I just assumed it was the coilovers. I did have the new tires on the car for about a week before I introduced the spacers and don't think I noticed any vibration. I guess it's possible I slung a wheel weight off when working on the car, will give it a shot with them off. C4S, and I think it looks perfect! Yes, using extended bolts that came with the spacers as noted.

I removed the front spacers, checked my wheels to make sure I didn't sling a weight or something, and went for a drive, noticeably less vibration, if there's any at all I wouldn't have called attention to it if I wasn't so hyperfocused on this right now. I noticed something that might very well be the culprit though. Are the spacers supposed to be flush to the edges of the hub in width? Would this cause something to be off balance? Do narrow and wide body 996s have different sized hubs?

Since most all Porsche's use the same 5x130mm bolt pattern, the spacers are probably machined to fit a variety of rotor hub diameters,ie Boxsters, 993's 944's 928's ect, should not make any difference. I suggest you read up on road force balance, the wheel/tire can be "ballanced" when rotating in mid air, but then be bouncing when on the ground due to varying roundness or varying sidewall stiffness. If the wheel/tire has varying roundness or sidewall stiffness the vibration will increase with spacing the wheel/tire further away from the mounting point thereby increasing the leverage.

Just swapped on another set of rims to the front that I've never had issues with, with the spacers, and experienced the same wobble. Will give a local alignment place a call about road force balancing, but maybe this is a suspension thing that's being exacerbated by the spacers? Like I said I do have a squeak coming from the front of the car under normal driving conditions. How can I check on the control arm/tie rod condition? I'm yanking the wheels from the side and top and bottom but it doesn't seem like theres much play...

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I know nothing about 'adaptec' as a company but your pic isn't doing anything to change my already generally low opinion of wheel spacers.

These cars a getting old and all suspension parts will be stiff (rubber) or worn. Maybe something your no looking at.

How can I determine if a control arm joint or tie rod is bad? I inspected them both and don�t see any tears, no movement of the wheel from left to right or top to bottom as far as I can tell.

C4S? did you check your wheel bearings?

I have spacers - 15mm front, 7mm rear - on my ME, with no vibration. Started with just 7mm on the front but decided that wasn't enough; with the current setup the Carrera IIIs fill out the arches nicely. If you've no vibration without the spacers I'd send 'em back and get a new pair, perhaps a different brand?

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Yes, C4S. How can I determine if the wheel bearings are bad? It's driving me crazy! I ordered these from motorsport-tech, they custom machined them for me so I'd be bummed if they were out of spec. I think my next step is going to be to measure them with a caliper to ensure they're consistent across. I do know that there is ONE little burr or piece of debris, maybe 1mm across that embedded itself into the backside of one of the spacers. I scrubbed it hard with a wire brush but it wont come off. Could something this minuscule throw off the balance enough?

The miniscule piece doesn�t throw off the balance, but it could prevent the spacer from sitting flush against the hub, causing the wheel/tire assembly to be cockeyed. That will cause a wobble.

^^^ cds72911 is right, the 1mm wobble at the flange will be 5-6mm at the tire tread. Jack the tire slightly off the ground and set a soda can next to it,spin the tire and measure the wobble. ANY measurable wobble will cause steering shake.

How many miles? The tt and C4S AWD cars seem to have a lot of problems with front wheel bearings. Unless really bad, I think it is difficult to check wheel bearings by the typical shaking of the wheel. IIRC, you may be able to check for roughness while spinning the hub without the wheel. You need to be careful when installing the lug bolts with spacers. Holes need to be lined up perfectly and lugs need to be seated properly. I use anti-seize on the mating surfaces which helps with hole alignment (i.e., slides easier). I am a little suspect with the spacer not being flush with the hub radial surface. Maybe consider what was already mentioned and see if the vibration exists without the spacers. If if disappears, maybe you need to get different spacers.

As an FYI factory spacers are 5mm and they also have two screws to hold them in place.

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I'll give this a shot, good idea with the soda can trick. 103k, and from what I can see from the limited service records I have, all of the original suspension components. There are 2 screw holes on the spacers for those "helper" screws that are on the hub, but I don't have extended screws for them, and I contacted the owner at motorsport-tech who said they're optional to use and wouldn't throw off the balance if I don't use them. For what it's worth he's offered to send me another set of spacers if they end up being the issue, but I'm going to go through and check some of these suspension things first.

I seem to forget a lot of details these days. I have the same spacers for my rear winter wheels (don't remember the size). And my spacers aren't flush with the radial edge of the rotor (not hub) either. I never had problems with vibration from the spacers. From what I gather, front bearings don't last 100k (mine didn't). To check the wheel bearings, you may need to remove the rotor to spin the hub to see if moves smoothly. But I don't think you mentioned where the vibration is coming from.

Okay, so I gave the wheels a spin next to a soda can, and there�s definitely some measurable wobble on the passenger side, not nearly as much on the drivers side. Does this indicate anything specific or just that something is off? Gave everything one last wire brush and swapped spacers from L to R in hopes that would do something but no dice. I�ve heard that bad control arm bushings can cause wobble, tried to take a look at the inner control arm bushing but I can�t really determine if it�s in good shape or not. Might bite the bullet and buy 2 new control arms, what do you guys think? Are the fork control arms necessary as well or are the lower coffin arms the ones that typically fail?

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If you swapped the spacers left to right and the problem stayed on the same side , it's not your spacers, it's your wheel, it's bent and the spacers is just exaggerating the issue..BTW, how much is this measurable wobble? Did you measure it ?..To confirm swap wheels from left to right and re-check. If the problem moves with the wheel then you'll know. Porsche wheels are very prone to bending after hitting big potholes, have seen hundreds of them bent. IF not bent to bad a good wheel shop can fix straighten it. Worn suspension bushings/control arm bushings will not cause the wheel to wobble just by spinning it by hand.. ANY looseness in steering/control arms/shocks/bearings will make it difficult to control the wheel and could cause a wobble especially after hitting bumps.

It seems like spacers place the wheel off-center with respect to the bearings. So even if there was no wobble, the wheel center is now no longer aligned with the center point of the wheel bearings, which can cause forces on the wheel bearings to be slightly greater. I guess that is one reason I have always been suspicious if spacers can create new problems.

It sounds like you may not be super familiar with the system, and you might benefit from taking it to a Porsche specialist? Rather than throwing parts at the problem, you might be able to narrow the replacement parts if a pro did the work. It might save you money in the long run.

Are you sure that it is not your "brand new" tires at fault? What brand of tires? You can check wheel trueness with a simple dial gauge and stand. Don't even have to take the wheels off, just jack up that side so you can spin the wheel with a dial gauge on the rim. That will tell you whether it is the wheel, tire or in the end, something else. Wheels and tires should not wobble.

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As stupid as it sounds, I didn't check if the problem followed the spacer to the other side or stayed with the wheel on the passenger side. After I came home from the test drive still experiencing wobbles, I called an alignment place and set up an appointment out of frustration and put the tools away. It does make sense though that if the wobble is there by hand, the suspension components wouldn't be the issue as they're not even under load. The measure was maybe about 2-3mm in wobble on the passenger side, maybe 0.5mm if any on the drivers side. Could it be a bearing issue? Do bad bearings spin wobbly? Fairly sure it's not the tires, as I swapped my old wheels back on that had never given me problems pre-spacers and experienced the same wobble with them. The new tires are Sumitumo HTRs. In any event, I set up an appointment with an alignment specialty shop to diagnose the issue this Friday. Tried to get away with being as cheap as possible on this one, should have known better

I had a similar issue. The farther you push out the wheel from the hub with spacers the more pronounced any imperfection or deflection from road services you will feel through the steering. I would definitely check to make sure the front wheels are "true" with no bends and balanced. The quickest way to do this is to ask a tire shop to spin it on their balancing machine and observe it at speed. Bends in the wheel can be both up and down from hitting a pot hole, or side to side. Once that fairly easy and low cost variable is eliminated, then I would move to the suspension. Replacing worn out suspension bushing is what solved my issues. I not only had a bad wobble due to adding spacers, but was developing a wobble under heavy braking. Felt like my rotors were warped, except they were brand new. I finally replaced my track control arms (coffin shaped), lower control arms ( Y shape fork), sway bar link, sway bar bushings, and inner/Outer tie rods. This solved all my vibration issues and the steering/control felt awesome. Like a brand new car! With 100k+ miles on your car and 14+ years old. All those bushing are seriously worn out or dried up. I would seriously consider swapping out those front suspension parts. Not cheap, but Made a really nice difference in the steering precision and steering tightness. If you plan on holding on to the car for a while longer... might be something to consider.

I have vibration issue on my 02 C4S (front drive disconnected) as well. I have new suspension installed all around at 107000 miles and the vibration did not go away. My front control arm bushings were fairly worn, according to shop that looked at it. The car has 5 mm on the front and 15 mm on the back, I think. I will be removing them and will try a different set of wheel/tire set after that. My car vibrates enough to be more than annoyance above 75 mph or so.

Maybe I�m missing something, but if the vibration goes away after removing the spacers, and it comes back with the spacers on, isn�t it clearly something with the spacers?

I chased down a slight steering vibration above 60+mph for past two months. First I thought it was alignment.....did alignment things where off slightly but not that bad. After alignment the vibration was still there now above 70+mph. I took the wheels/tire to wheel shop and had them checked.... everything was fine. I checked all the suspension components and found the lower control arm ball joints very soft/loose. So i replaced both front lower control arms. Vibration was still there above 75+mph. I just thought it was more to do with roads then anything else.....we have horrible roads in the northwest due to winter tire studs. Was doing brake job so i decided to check on wheel bearings. Both front wheel bearing had the tiniest bit of play. The rear wheel bearings where tight and smooth. Long story short I changed both front wheel bearings and now the steering vibration is gone..... even up to 115+mph!

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I�m leaning towards replacing everything for this reason, the age and wear is undeniable and if I�m going to go in there and do one thing I might as well take care of it all. I gave it a test with the spacers off and now that I�m looking for it, there is an extremely minimal vibration even with no spacers. Nothing I would have noticed before all of this, but it may be time to do some refreshing of components. Based on the wheel spinning test I did with the car in the air, this seems like the most logical issue, a worn bearing with a little bit of play would cause it to wobble under no load, is that correct? Tempted to cancel the diagnosis appointment I set up, to pay to have them tell me something I already know!

Following up on this for anyone interested, took it to an alignment specialty shop, and road forced balanced it. Almost fixed the problem entirely. We did notice that one of the front spacers was still causing a wobble though, confirmed by swapping it side to side and measuring the play. Had motortech-sport send me out new spacers and I'm 100% vibration free now. Seen so many threads like this that end up with a road force balance fixing it all, I guess I shouldn't be surprised Thanks for your help everyone!

Glad to here you got it figured out. Thanks for updating the post!

Just be careful with what you drive over at speed, i've got a number of small stone chips on the side of my car, even from my genuine factory "approved" 5mm spacers... They do look good though!

My wheel weights fell off, got them rebalance, viola! All good now!