I just picked up my 2014 GLK350 this Wednesday and noticed yesterday that whenever I turn the steering wheel slowly within a couple degrees of the turn there is a high pitched noise. I brought it into the service department and they said everything is good with the car.

What should I do? I don't know if the dealership is giving me bull or not. Though the sound only last a 1-2 seconds its really annoying.

Anyone have advice?

What do you mean when you say "whenever I turn the steering wheel slowly within a couple degrees of the turn"? Are you turning the steering to full lock or close to it? If you are you are building up pressure in the power steering system and the relief valve is opening and they make a high pitched screech as the fluid moves through the valve. This is not very good for the power steering system. If this is what you are doing don't turn the steering so far over and back it off some when you get the high pitched screech until it ceases to screech.

No I am not turning it to full lock. I turn the steering wheel very slightly. If we look at it like a clock, I turn it to 3 o'clock on the right and 9 o'clock on the left

Not sure what is causing it but it sounds like something in the steering may be binding. That cannot be good and not normal sounding. Can the dealer reproduce the sound? If it continues I would take it back and go for a test drive with your SA or a tech. Once they have reproduced the sound with you in the car it should be up to them to resolve the issue.

I did take the car to them yesterday and they did reproduce the sound and both my sales rep and a technician said t was normal.

Should I take it to a outside shop for a second opinion? Or to another dealership?

Are you experiencing this while driving or while dry steering? Vehicles really don't like having their wheels turned when they're not moving.

Driving at VERY LOW speeds such as turning into a parking space or turning right after a stop or turning out a drive way.

I'm still ignorant on many parts of the GLK, so will learn more when we pick ours up this week... but from past experiences I'll take a few guesses:

1. Power steering fluid is bad
2. Power steering fluid isn't full and allowing air into the system
3. Power steering pump is on it's way out

Number 2 isn't the hardest to diagnose, sometimes just bleeding the fluid a bit can solve this one, and then of course topping it up. If the fluid is normal, it might be worth having them flush the system and replace with new fluid.

What do you recommend I do?

Sorry about that, I had edited my post and added a bit more detail.

Since the dealership tech told me that my car is fine, how do I make them flush my system?

That's always a tough call. A lot of dealers don't want to do the diagnostic work since they don't usually get paid for the time spent. They like billable warranty hours, which this probably wouldn't fall under.

I'd just say hey, I know you've said the car is fine, but the noise is still there. Can someone come for a ride with me and I'll reproduce the noise? I've also been doing some reading on similar issues and a lot of folks are saying that these are the items which might need a closer look...

Hmnn...I thought the GLK was electric assist and not hydraulic...

Normal horsecrap. Try another dealer or an independant shop. Also find another dealer for your next purchase. That guy is a sleezebag same as mine was. Never been back. In the old days that squealing was a loose belt. Might try a little spray belt dressing and see if the noise goes away for a while.

Does the car need to be moving? If so, it probably is drag on the brake pads or a slight vibration from the backing plate. Even stopped the wheels rotate slightly when the steering is turned. If not it may be a bad bearing in the belt idler or the alternator. Check that the belt tension is correct and that the alternator clutch in the pulley is working correctly. The electrically assisted power steering may put a large load on the alternator at low speed, but you would think that would show up with the car stopped. does it go away when the car is warm and that is why the dealer doesn't hear it?

The car can be both moving and sitting still. Actually the dealer did hear it, and they assured me that it was okay.

Andrew,

Could you get your dealership to let you listen to a similarly equipped GLK that they have new? If you could simulate the same noise on one or more new models on their lot, then it's normal (probably). Depending on how they respond, you could always suggest that you will not have very good things to say on the all-important dealer survey that you should get soon. Hopefully you haven't completed it yet!

You will probably be getting multiple phone calls from different areas of the dealership prior to getting the survey, so sound off about the way things are being handled to whomever contacts you.

I'd try to play nice, until I found out for sure if your noise is normal or abnormal. It does not sound like you have any evidence, except the service department's opinion. They need to do more to convince you what is normal.

Just got back from two individual Mercedes specialize shop and both confirmed that that sound is suppose to happen and all is well with my car.

Thank you everyone for all the help everyone

I need some fluid also...there is a brown and also a green...anyone know which is right for our car?

That just means there is an electric motor that drives the hydraulics instead of a belt-driven one.

Nope no fluid
http://www.caranddriver.com/features...n-test-feature
You can see many components could produce the noise.

pg 334 owners manual
Power steering All models approx. 1.1 US qt (1.0 l) MB Power Steering
Fluid (Pentosin
CHF 11.S)