YoussefAbe

Hello,

I have a 2009 C300 4M, and when I drive over 60MPH the car and steering wheel shakes heavily, to the point i notice my passenger side headrest shaking. I went to a tire shop and balanced my tires, but no improvement.

What do you think it can be? Thanks in advance.

janusgrimnitz

do u have spacers?

Carsy

Did the symptom begin suddenly (Bent wheel?) or progress over time (worn suspension.) ?

edgalang

Wheel already shop balanced the wheels? Then my next guess would be you have aftermarket wheels and you don't have the proper hub centric ring.

95Sinned420

If tires are balanced, wheel isn't bent, next part would be suspension components. I would assume it's not a hun ring issue because that would've occured a long time ago if you put non-hub centric wheels on. If it's just occurring now, then it's unbalanced tires (which you corrected), bent wheel (tire shop that balanced your wheel would've caught it), worn suspension components (everything from bad bushings to loose ball joints, etc), and even driveshaft (does it go away in neutral?).

From experience, when I had that violent of a shake, to where the passenger seat was shaking, the issue was bent wheels.

TheRulesLawyer

Thing is if a shop balanced a wheel they should have checked for a bent rim. Something that bent would be pretty obvious. Same with hubcentric rings. Its unlikely they got taken off and put back on again that badly. I wouldn't rule out bent rims, but I'd slap the shop that did the balance if they didn't catch it.

If it changes when you're on the power vs off it'll tell us something.

YoussefAbe

No spacers,

Began suddently

Factory wheels, new tires since last august.

Tire shop checked everything, all looked good. I had a small bubble on the sidewall of my right rear tire (really small bubble)

The problem goes away in neutral, or driving under 60MPH

Carsy

Engine or gearbox mounts or clutch if manual.?

edgalang

My next guess would then be cupped tires, but TheRulesLawyer is correct in that the shop should of noticed that as well.

With that ruled out, my next guess would be flat spotting and that MAYBE you live in a cold climate where the tires are parked overnight?

Carsy

Edgalang, There is no vibration in Neutral.

edgalang

Bah! I missed that detail. In that case, my personal knowledge base has run dry.

Critter

If you can move the steering wheel a little side, say to change lanes and the vib stops momentarily you may have a worn wheel bearing or as you say the vib goes away when in neutral, look into the front drive shaft CV joint.
Just how much weight did the shop use to balance your wheels?? Is there one on the front with say over 4 ounces?

YoussefAbe

So it turns out most of you were right...

I took it to a Indie shop and he rebalanced the tires, and said the rears he had to add much more weight than what was already on before. He inspected the rim and he said its a little damaged (not cracked, just really scuffed up badly.) Also on that same wheel my tire had a bubble on the inner sidewall.

I ordered a replacement tire through Discount Tire Direct and should be coming in the next few days. But for now the steering wheel does not shake anymore. Thanks for all your help