lexaltezza

I've been trying to solve this vibration issue for over 6 months now and it's driving me insane! What's happening is that around 75mph-80mph on the highway, I can feel a slight vibration throughout the car. Enough so that my rear view mirror shakes to the point that everything behind me looks blurred.

I've taken in to the dealer, but they say they are not allowed to drive at those speeds. So they offered to do a wheel balance and it actually seemed to solve it for about 2 days and now its back again. It really isn't so much the vibration, but more so the sound accompanied by it. I've made a previous thread about it, but I swear it sounds like the wind is making a "flapping" type of resonating sound. I can even hear it over the radio. My only guess was that it was tire related, but I've had the tires changed recently, even to a different brand, and seem to still have the issue. I'm clueless and the service dept. is clueless.

If there were something I liked to trade it in for, I would do it in a heartbeat because of this damned annoyance!

Can someone here drive 80mph and see if the car is quiet and vibrationless?!

Blood Doctor

never experienced that... sorry to hear you're experiencing it.

I make mad dashes to the local mountains / desert from time to time and haven't had any problems or vibs at high speeds. Wife is always amazed how the CLS seems so solid & confident at high speeds compared to some of our other cars.

At low speed, I get the occasional "clunk" in the rear which is the air suspension not fully loaded at times, which bugs me for a car of this caliber.

Good luck... must suspension issue if you've already ruled out your wheels / tires.

JustPete

Is this with the windows down only?

Turbulence is the culprit. Some cars get this REAL bad at speed. The turbulence can turn into feeling like your inside a kick drum being pounded rapid fire.

Close the sunroof and roll up the windows. If it goes away, you found the gremlin.

hcetzneb

If you already changed the tires then i agree with justpete it sound like a turbulence problem. I cant help but notice the aftermarket bumper with very aggresive air ducts.
Did you notice this vibration since you put the new bumper on... ive seen some carlson bumpers make wind noise

mbenz1

Instead of trying to figure it out yourself, why don't you drive the car and invite the shop foreman to ride with you on the freeway?

turbotom1

Well the vibration is not normal for only 80 or even 120, trust me the CLS is rock solid and stable at speed.
Could be one of several things.

Check the wheels for stones, nails etc.

Get a wheel alignment, check the rims - twice - or drop them off for testing.

Take the car to a shop that offers "High speed on the car wheel balancing"
http://books.google.com/books?id=9tC...ncing&pg=PA122

http://eastcountyalignment.com/newpage4.htm

I get turbulence around 40-50 and just crack one of the rear windows.

High speed vibration is often an indication of a wheel that is out of balance or a bent rim. It can also be a bent driveshaft or bad U-joint.

lexaltezza

Boy I wish it were as simple as rolling the windows up! It is with the windows up. Based on your description it is similar to a kick drum in that it's like a deep oscillating bass pounding in your ears.

I had the problem before I had the Brabus bumper installed unfortunately.

I've tried to do that on several occasions, but never could at that particular moment. I may need to try again.

I have had an alignment done too recently to no avail. The on car balance as per your link sounds like a good idea. That sounds kind of unsual for you to get turbulence at 40-50. Have you had it looked at?

Thanks for all of your help and suggestions so far guys.

JustPete

That's turbulence. I didn't notice that front bumper. Obviously not wind tunnel tested. When you hit that speed the buffeting begins to resonate I'll bet. You feel it right in your skull, don't you?

turbotom1

Its kinda more like a resonance at that speed and all you do is crack a rear window and it stops. Happen on my Jaguars too so Im used to it.
Too late to get it fixed as I just ordered an 09 CLS63 this morning. Diamond white metallic with ash interior and led tail lights.

You will notice immediately that "on the car wheel balancing" makes for a smoother ride, even on a car just balanced.


http://customwheelsmarket.com/diwhvi.html

http://www.markwilliams.com/balancing.aspx

hcetzneb

Just a though before you go insane with on car balancing and stuff just take strong tape (200mph tape ) or painters tape and cover up the opening in the bumper completly and see if the vibration get better/diffrent if so i wouldnt go crazy with all the balancing and stuff.
Like you said you have brand new tires and it didnt change at at.. it would of changed the vibration some what if that was the issue...

also im not sure if you answered the ??? did you notice this issue after the bumper was installed ???

Dogshine

I know you say youve balanced the wheels, but I bet one of them (sounds like a rear) is bent and it causes the vibration. I have felt that happen before I switched out a wheel.

proform

Bent Wheel

JustPete

Pretty hard to balance a bent wheel. When they see how much weight it takes to make the wheel balance ... that's usually a dead giveaway.

Kenny Pollock

Not true... some shops have their own "threshold" and will balance a bent wheel no problem as long as it's barely bent. Bent rims are the worse. $100-$200 per rim to bring back to new.

JustPete

What I mean is, when they balance it, they should have told him if one was bent. I don't think he said they had any problem with it.

lexaltezza

The rears are brand new with about 2000k miles on them so I don't think that would be an issue. I should check for even wear out though.

It definately feels wonderful. I'm sure the front bumper is wind tunnel tested considering it's on the Brabus Rocket which can hit a top speed of 227 mph.

Love the led's, wish I had them. I'm hoping to find an on car balance somewhere nearby, but haven't so far.

I had the same problem before the bumper install.

It's possible it is a bent wheel. I might try and get it rebalanced and have them check for it.

JustPete

You're right. Saying it wasn't was a bit off the cuff. I guess what I mean is not for a daily driver that would cruise at 75-85mph which is where the turbulence begin to resonate. Past 100 they probably stop again.