Knocking noise when turning steering wheel at full lock?

[DLB94]

Hi,

I've recently picked up a C200 (2017) from a private car garage - I've noticed a knocking noise when turning my steering wheel at full/almost full lock.

Initially noticed this when making a pretty tight right turn and also noticed it when going around a roundabout. The noise seems to be coming from the front right wheel.

If I make a normal right turn, it doesn't make a noise, only when the steering wheel is close to full lock.

Can anyone help please?

 

[markjay]

In my case it was the front strut top mount rubber bush, but it could equally be the hyro-bush on the camber control arm, or any of the ball joints or drop links etc etc. Or the front strut top mount bearing.... or a broken spring... it really needs to be checked properly, and you may need to replace parts in an exploratory manner before pinpointing the culprit. And keep in mind that suspension components are best replaced in pairs, even if the other side seems sound... good luck.

 

[markjay]

Seeing that you are based in London, consider going to see Terry Gates at Wayne Gates Wayne Gates Specializing in Mercedes-Benz Servicing & Repairs, or better still a trip to see Tony Bones at Wheel Alignment | Tracking & Steering | Blackboots Tyres Chesham . Tony will also be able to carry out a full geometry alignment while you're there.

 

[optimusprime]

You will get this if its on full lock .Manual said not to do this full lock thing

 

[Linksdale]

I have just seen this old thread. I suspect the problem has been solved by now but this update may help others. Depending on exactly how the noise sounded, at low revs and full lock, it could be the serpentine belt "slapping". If so check idler/tensioner wheels but more importantly check the alternator clutch pulley is not seized. It seems odd I know but this pulley is an important part of the belt system and can cause a host of seemingly unrelated problems/noises. It is also missed/neglected by far too many so-called professional mechanics. There are many explanations on the web about this pulley, what it does, why it does it and how much damage it can cause if it does seize. Sorry to be a bore!

 

[optimusprime]

Linksdale You only use the steering on full lock for a few seconds only .

 

[markjay]

Thanks. My C180 has electronic PAS, not hydraulic.... and in my case it was front suspension components that needed replacing.

 

[optimusprime]

Mark i am still in the past my friend .. nice to know you have fixed it .

 

[markjay]

Mark i am still in the past my friend .. nice to know you have fixed it .

I did... in 2017....

 

[slipons]

It sounds like the tyre is rubbing on the wheel arch liner on full lock. Does the car have the standard wheels fitted? or aftermarket ones?