Hi All,

I've been hearing this humming/grinding noise coming from the center differential whenever I take 90 degrees turns (left or right) at slow speeds, it happens intermittently which makes it hard to replicate when I took my car in for it's 15,000KM service.

Has anyone had any similar experience ? By the way, my car is equipped with PTV+.


TIA

 

When I make a left turn gradual left turn, like at a stoplight when slowly accelerating, I get a grinding noise from rear. Seems to happen from cold, or first starts.
Is quite noticeable I've had passengers ask what's that.... Ummm

Almost daily, but only with initial starts. 40 degrees outside to 100 degrees.

 

Thanks for your reply. My dealer has checked the car, didn't find any unusual noises as per them, but it is there.

Well, let's just wait and see, it might get worse with time.

 

CTT-QTR,
Why didn't you test drive the car with the mechanic at the dealer? Can you reproduce the problem?

Jace,
Have you contacted the dealer yet? Let them know the problem and request to test drive the car with a mechanic on board.

 

Almost daily Jace?
I have never noticed this noise,though I do have the music on most of the time when I start
Will be on the lookout for it from now on...

 

I have this same issue. I asked my dealer about it and they have no idea what it is. I am thinking it is being caused by the PTV.

 

Thats what I did, couldn't reproduce the noise and they tested drive the car while it was there (fixing some other issues) no unusual noises were heard.

Yeah, I guess too.

 

I have an appointment for this week.
You can feel the grind-ish when slowly pulling away and making the turn.
Goes away once getting straight. And gone once warmed up and making those same turns.

Once sits, does it again.
We'll see.

 

Mine does it when it's fully warmed up.

Let's us know how things go.

 

I don't know if this applies to you, but I had a similar grind that I could not reproduce either. I figured out it was the PDC kicking in whenever I was turning and I got too close to the car in front of me.
Obviously it would not be the same issue if you guys do not have PDC.

 

[QUOTE=CTT-QTR;3625479]Hi All,

I've been hearing this humming/grinding noise coming from the center differential whenever I take 90 degrees turns (left or right) at slow speeds, it happens intermittently which makes it hard to replicate when I took my car in for it's 15,000KM service.

Has anyone had any similar experience ? By the way, my car is equipped with PTV+.


My CT has had a whining noise for last few months.
It's there even when you rev the engine.
Today the whine turned into a bad grinding noise.

It sounds terrible especially in the first 4 gears and under acceleration sounds like the engines turned into a deisel.

Anyone one else has this problem.

Off to the dealer again tomorrow.

The 958 has been the most unreliable Porsche I've ever had.

 

having the same problem..

grinding noise at 90degree turn after cold start...
had it reported to mechanics! and they told me its from the front diff..
had it replaced my warranty.. but it got worse now..
the sound didnt come after the car warmed up before..
now its there every time i do a slow turn! after cold start and at warmed up stage...

hope porsche comes up with some recall..

 

So you have replaced the front diff and the noise got worse? I suspected that my diff was shot, but now it seems it's something else causing this. I'm going to get this checked next time I take my car in.

Some 991 owners have reported similar noise with their brand new cars, and according to many it is normal.

 

Could it be the noise of the rear brake when PTV plus doing its job at times when making sharp turn?

 

I don't think so. It makes the noise at low speeds (parking lot speeds) when making 90 degree turns. No noise whats so ever at speeds higher than that.