2012 SLK steering vibration

[AlexJReid]

Feel like I've been fobbed off a few times by the dealer and MB themselves over this so gave up on the issue for a few months. But it's starting to annoy me again!

I have a 2012 SLK with 7000 miles. I'm experiencing some vibration through the steering which doesn't always happen. Sometimes it's bad, sometimes it isn't that noticable. The wheels have been rebalanced several times, which didn't help.

At around 60mph the steering becomes quite light and there's a definite shimmy in the steering wheel which is most obvious when steering in either direction. The speed at which this happens isn't always the same. The car requires more effort than I'd expect to keep straight.

Today I noticed that there's a bit of a clunk when moving the steering with the ignition off (steering lock off) when stationary. The noise isn't the steering lock. I do wonder if there is some sort of play in the steering that could cause the above?

Any advice appreciated.

(Rubbish video, sound like really audible: http://www.youtube.com/watch?v=7o8LwVlAphk)

[nsa]

These are the causes I've personally had for vibration through the steering wheel:

1. Warped brake discs - virtually undrivable Jeep Cherokee. Think I was roasted by the dealer though. £350.
2. Unbalanced wheels - common, sometimes requiring more than one go to fix.
3. Bent wheels - can't be resolved through balancing. Sorted after wheel straightened.
4. Flat spotted tyres after track driving / storage. Works itself out.

I wonder if yours isn't something to do with the steering wheel linkage though. Bushes, rack etc. Idle speculation.

[one eyed mick]

I would hope on a 7k mileage hispec car that nothing is worn to the extent of giving these probs ,wheel runout ,or a badly fitted or distorted tyre , kerbing damage ,these have got to be the route to take .Try another or indy merc specialist ?

[The Wookie]

I very much doubt there will be anything up with the suspension on an almost new car like that.

Could it be that the tyres have flat spotted from being sat for a while? Particularly if pressures have been left too low. If the car was a pre-reg or bought from stock it's possible this might have happened before purchase.

Also worth pointing out that I've experienced tyre defects from top branded tyres on new cars before.

Might be worth swapping front to rear if they're not staggered just to rule it out. Even trying left to right might be worth a go to see if it makes any difference.