Rear low frequency Humming at 50-60 mph

Matrixxxx · 7 Feb 2020

I'm getting a low frequency hum that starts at 50 and peaks at 55 then goes above 60mph, it sounds like its coming from the rear, no vibration , but some times its not there at all.
I suspect the rear outer CV joint passenger side , anyone had this?

moorhouse · 7 Feb 2020

No experience of the Cayenne but just a thought - have you checked the tyres for "cupping" or "castleing"I think it's called - has exactly this problem on two of our A3s with their original low profile Continental tyres and drove me nuts trying to trace the source of the noise. Like you assumed it was a wheel bearing but didn't follow the usual pattern of increased rumbling noise when weaving slightly to change weight distribution to each side. Apparently happens to some tyres/car combinations where the centre part of the tread block wears more than the edge leaving a "wavy" feel as you run your fingers around the tread. Basically then sets up a resonance at speed. Apparently happens with certain Vectras etc. as well. As I say, just a thought and might not be a thing with Porsche - certainly never had it in the 996.

Cheers.........Ian

golfprorich · 7 Feb 2020

I'd agree with above, definitely check inner edges of the tyres. My Vectra use to do a set of rears in no time until I had the camber reduced. The noise was exactly as you describe :thumb:

Matrixxxx · 10 Feb 2020

Its a possibility, but I have put a set of winter tyres on, and they make the same noise, but they came from a older cayenne so could have the same problem, but the sound does not change on different road surfaces , which previous bad tyres I have had did.

rickprice · 10 Feb 2020

My money would go on wheel bearings.

Rich

Matrixxxx · 9 Mar 2020

Checked all the drive shafts while fixing my exhaust , all the joints are very solid not even a hint of play, all the boots look like new, and it looks like the cardian shaft centre bearing support has been changed at some point.
it may well be the tyres as the noise seems to almost disappear after 30mins of driving ,on a previous car I did have some Verdistien tyres that would flat spot because of the soft compound, they would clear the noise after 15miles of driving, I also remember people saying that they had the same issues with Porsche rated tyres.
the winters will be coming off soon so I will see what the change is, although I have noticed that the Michelin latitude 3 tyres have 2 pairs of different N ratings.

Rear low frequency Humming at 50-60 mph

Matrixxxx

Trainee

moorhouse

Montreal

golfprorich

Trainee

Matrixxxx

Trainee

rickprice

Monza

Matrixxxx

Trainee

Similar threads

Latest posts

New Threads

Porsche Model Range

Porsche 911

Porsche Hypercars

Other Current Porsche Model

Porsche Legacy Models

Forum statistics