mint

I'm hoping someone can help throw a few suggestions as to what may be causing my current wheel vibration. I'm at my wit's end and about to go crazy -- here's the backstory:

My CLK320 convertible was on OEM 16", had no vibration, and everything seemed fine (I say seemed because I may have had a slight problem and the thick OEM tire sidewall masked the problem). About a month ago, I put on new wheels (Forgestar F14 with Nitto Invo rubber), lower spring pads on the front, and Eibach Pro Kit lowering springs. Now here's where the problems started. Ever since I put on the wheels and springs, I've had a vibration that has progressively gotten better as I fine tune a few things but still hasn't completely disappeared and it's bothering me. The things I have done to try and cure the problem:

- hub rings on the wheels are a tight fit against the wheel hub and hub bore on the wheels
- lug bolts are the correct seat, length, and torqued to spec
- wheels have been tested on a Hunter GSP 9700 for runout and are definitely within spec
- wheel/tire assembly have been road-forced 3 times to acceptable limits
- alignment done by dealer and checked out okay
- suspension bushings are all good
- tires check out and are in great condition, no bulges or shifted belts

After all these attempts to fix the problem, I've noticed the vibration has gotten noticeably better but it still lingers. These are the vibration symptoms:

- present 60mph+ which I know, sounds like a wheel/tire imbalance but as I stated before, I've gotten them road-force balanced three times within acceptable specs
- I can feel the vibration through the floor, through my seat, and to a much lesser degree the steering wheel
- at lower speeds I can still feel the vibration and it is speed dependent and in-phase; the vibration almost feels like it's rubbing but I've checked and there's nothing that is rubbing against the wheel/tire assembly
- the vibration feels like I'm driving on gravel, if that makes any sense; the accompanying noise from the driver's front assembly in the cabin sounds sort of like a whirring sound
- it is most likely nothing to do with the drivetrain as I've shifted into neutral while it was occurring and the vibration didn't go away
- at my indy shop (who is the only authorized Kleeman installer in my area) when the car was on a lift and you spun the two front wheels, you could see the slight lateral run-out on one wheel and slight radial run-out on the other. Again, I had the wheels tested for run-out and they were definitely within the range of passing

So I have no idea what could be causing this. My current thoughts are:

- hubs on the wheels might not be true
- hub assemblies on the car might be off (hell of a coincidence that both fronts are off)
- bent axle (I can feel the vibration in my seat and the floor, so really, two bad axles?)
- something else?

The "something else" is where I need your guys' help on so we can try to pinpoint the problem. I've nearly exhausted my options -- any feasible suggestions you can toss around would be of great help and I'll keep an eye on this thread to post responses.

Thanks!

mint

Well, last night I switched my wheels with a friend's 18" Mono Aero IIs and I have the same exact problem so I don't think it's the wheels so much anymore.

I'm taking the car into my indy to comb over the entire front suspension; my instinct is telling me a bad wheel bearing, tie rod ends, or control arms/control arm bushings.

Ghostrider

You're brake rotors may be warped.

dlbehrns

can we assume the vibration did not exist before? does it vibrate with the convertible top up and down.

big_mike1979

bearing or rotors

mint

Wouldn't the brake pedal pulsate when I brake if this was the case? Because I don't really feel a pulsating sensation when I apply the brakes.

Also, when we switched wheels while my car was jacked up with the Forgestars, we spun the driver's front wheel freely and could hear something going on with the rotor (i.e. rotors rubbing on the pads or something).

Before I installed everything? I didn't feel anything like I do now but I can't confidently say it for sure wasn't there before as the OEM tire sidewall is much thicker than it is now and could have hidden the problem all along.

My friend reference cowl shake/chassis judder and I don't think this is the case. It almost feels like my wheel's about to fall off.

mheffel

Sounds like wheel bearings to me.

Chappy

Steering damper....has anyone mentioned that? Could also contribute.

mint

Yes, thank you.

To keep everyone up to date, this is what I'm going to specifically have my indy shop look hard into even though they're going to comb the entire front suspension:

- wheel bearings
- steering shock
- rotors/calipers/pads
- axles
- control arm/bushings
- hub assembly
- tie rod ends

Chappy

You don't mention how many miles are on your car. When adding lowering springs, did you change your dampers too? If not, they may be shot.

I would put your 16s back on and see if that changes anything.

mint

83kish.

No, I didn't change the stock shocks but I'm confident that is not the problem as my ride quality isn't bouncy nor does the suspension feel like it's hopping; I've loaded each corner and the shocks did their job within 1.5-2 oscillations. I suppose I should have my shop check the shocks to make sure since they'll be looking around there anyways.

Haven't had a chance to throw the stock 16s on yet -- I'll probably get around to that this weekend if the shop inspection doesn't reveal anything out of the ordinary.

503benz

I have the same problem with my 03 e320 too. I put new 18" wheels on an start feeling the vibration and squeezing noises. Ii take my in and they said my ball joints are bad and lower control arms need to replace. I replaced both control arms and ball joints . But the vibrations and squeezing doesn't stop. Don't know what I should do next.

Worth the wait

What run out are they using on the Forgestars?
Seems the spec needs to be especially low on the Mercedes cars that go plus on..or two

Good luck!

mint

Well, I would try to isolate the problem first. Do a swap with someone who has 18" OEM wheels that run true on their car; if you don't feel the vibration, then it's obviously your wheels. If you do feel the vibration after the swap, then it's most likely the car.

A few preliminary questions that might help: are your wheels aftermarket? Do they require hubcentric rings? Are these rings snug on the wheel hub as well as your vehicle's hub? Are you using the correct lug bolts (cone vs. ball seat, length, bolt diameter)? Have you gotten your wheels and tire assemblies road force balanced (this is not the same as a regular balancing)?

If you've done everything above and still have the problem, then you're in the same boat as me. Your best bet would be to have a good shop that knows Mercedes well to diagnose the exact problem, otherwise, you'll just be throwing random parts at it to fix.

It also helps to do some research on the internet to pinpoint possible symptoms (sound the vibration makes, where you feel it, steering wheel vs. chassis vibration, context on when the vibration happens). In my case, I think I've gotten it narrowed down to tie rod ends, wheel bearings, or possibly a rotor/caliper misalignment.

Good luck.

mint

From my research, the Hunter GPS9700 goes by a 0.03 inch runout spec for both lateral and radial for aluminum/alloy wheels -- steelies have a different runout (I want to say 0.04" for lateral and 0.045" for radial but don't quote me). Also, Luke @ Tire Rack said the same thing...a wheel with 0.03" of lateral/radial runout is a very, very true wheel and you shouldn't be seeing nor feeling any sort of vibration related to the wheel if yours falls at or below the 0.03" spec.

I've had my wheels and tires road force balanced on the Hunter three times, and the last time I had them give me a printout of the runouts. From what I can tell, my wheels are extremely true and straight. I don't have the Hunter printout with me as I'm at work but I can work on getting the exact runout numbers posted if anyone's interested.

Chappy

I'm really really really really picky when it comes to steering wheel vibration.

Suffice it to say....even running OE monoblock IIs with Michelin PS2s....I had a vibration. I took it back and the service manager at MB took care of me. They re-checked the alignment and re-balanced the front tires. The second time, they got it perfect.

It could be the wheels....it could be the tires....even if they are only one ounce off, you'll get a shimmy.

Good luck and let us know your outcome.

big_mike1979

keep us updated. im curious to know whats your prob. it could be also from tires. if they are worn from the inside and u got thin profile like 35 or 30.. the car ll vibrate even your steering wheel. my car vibrates lil because i got the slotted drilled rotors when i apply brake.. my best bet take it to benz dealer and let em look at it and fix it at your boys shop. u ll spending too much money changing parts and yet u can't find the prob. good luck again.

kiwikompressor

Hi have you had the wheel balanced on the car? This will tell if its a hub etc.
Have you checked if the tyre is round? They can go out normaly cheap tyres but good ones too. When they aren't round they can still be balanced but you have to eye ball it on the machine. Good Luck let us know your progress

mint

Well, turns out nothing was too out of the ordinary as far as suspension -- the driver's front wheel bearing was a tad bit loose so they tightened it down. Didn't really help all that much, so onto seeing if my wheels are even straight. My shop pointed out to me yet again that when the car's on the lift and they spin the front wheels by hand you can even see a radial runout on one and lateral on the other; that can't be a good sign.

I would hope it's not the tires -- they're brand new Nitto Invos and looked great on all the insides. Running 225/40 front and 255/35 rear which doesn't seem excessively thin.

I haven't thrown too much money at this problem yet, just a lot of wasted time going back and forth figuring out what it is.

I'm going to a wheel repair specialist or a shop that specializes in tire/wheel sales to help me figure out what's going on.

mint

Changed back to the stock 16s -- there's definitely something wrong with the aftermarket wheels as the vibration is almost non-existent and yet, still there (yes, I'm super picky but it didn't do this before I changed my wheels ). Also, noticed some sloppy steering feel, weird grumbling/creeking and squealing sound when I turn along with the 65mph+ shimmy. The Forgestars definitely amplified all the issues.

I think I have it narrowed down to the steering shock, tie rod ends, control arms, rotors/calipers/pads, or control arm bushings. Not satisfied with my latest visit at my regular shop so I'm going to another shop that's the top rated Mercedes specialist in the Sacramento area to see what they can find.

Chappy

There was another thread where someone had issues with the same wheels you have.

https://mbworld.org/forums/c63-amg-w...uspension.html

If your wheels are not hub-centric and require different bolts, this may only add to your issues.

mint

Yeah, I already knew about this in advance before I got the wheels. The hub rings I got were fairly snug (less than a mm of play) so that could possibly be it in addition to the inconsistent build on the wheels. It wouldn't explain why there's some sort of physical axial runout on one of the fronts and radial runout on the other; I haven't even bothered to try spinning the rears on the car for obvious reasons but I assume the same problems exist for the rears.

Interesting story about my wheel seats: when I had the cone seat lugs on as is standard with most aftermarket wheels, my shop informed me that the wheels were actually ball seat. Sure enough, I called up Forgestar and they had a short production run (they said ~20 sets) where someone messed up and got ball seats instead of cone seat. Of course, with my luck, I got one of these sets and ran with the wrong lugs for a while so needless to say, I'm not happy with their QC at all and wouldn't be surprised if the wheels aren't even true.

Also, per my last post -- still have the same problems with the stock wheels, though greatly diminished. In fact, it is so minute that perhaps the problem existed before I changed my springs and wheels and I adapted. Now I'm just more curious than anything about what it could be.

badblackbenz550

I have the same problem, i fixed all 4 bent rims and the shaking is still there, so i just purchased new rotors. After i install them i hope all the vibration stops.

Supafly

I'm going to suspect a outer tie rod or a bent hub assembly....

I had a slight vibration in my steering wheel on a w209, and after inspecting all the bushings/wheels by the only qualified AMG specialist in Canada; it was deemed that I somehow had bent the drivers hub assembly and thus creating a slight vibration while cruising aprox 80km/h....we swapped out hubs, and voila...no more vibrations...

ask ur indy mech to measure the runout on the hub assembly on both sides....

mint

Update:

Took the car to get the suspension inspected at a second MB indy shop and owner said everything looked good. He did mention alignment felt off and to get the stock 16s rebalanced. So I went to the local tire shop, got realigned and rebalanced and the high speed vibration went away and the steering feels a little tighter. I guess that goes to show you if you're lowered, MB dealership might not be your best bet as all they're going to do is just get you as close to OEM specs as possible instead of optimal primary angles.

In conclusion to this thread: the most important thing to me is, the high-speed vibration has gone away. As far as my continuing dead pedal/accelerator vibration, maybe I'm too **** but I don't think so. I'm going to be making a 900 mile drive for Thanksgiving so maybe something still has to settle in from the lowering springs...who knows?

All I know is, I'm wasting way too much time, money, and energy on chasing the cause of all this so I'm pretty much over it for now. If the car vibration still bothers me come early spring, I'll probably have someone rip out all my suspension at my next scheduled servicing and check every single thing, from the driveline to the hubs. After having two MB specialized shops tell me nothing is wrong, it can't be anything too serious; as far as something being busted, I guess I have nothing to worry about.

Thanks to all for the suggestions and help.