Grinding Noise

[Gomev]

If you Google this condition, it pops up straight away.
There is loads of info on this condition which is wide spread on a number of cars with trailing wheels ( FWD ).
Here is just a quick snippet of why this happens, note the date on this service bulletin!. 2008 !.

Technical product information Transaction No.: 2019800/1

Saw Tooth Tyre Wear Release date: 23-Dec-2008

Customer statement / workshop findings
Saw tooth tyre wear / tyre noise.

Technical background
A Major cause of annoying tyre / road noise is "Heal and Toe wear". This is the outwardly visible (and audible) manifestation of various distortional forces at work on the tread. To explain this, it is better to first say something about "tread design".
Tread grooves and sipes - a source of noise - are absolutely essential in ensuring safety on wet and flooded roads. In the case of low profile tyres in particular, a higher percentage of tread void is necessary to take up and channel the water, while a hydrodynamic tread pattern design is needed to ensure water displacement.
The upshot of this is "detached blocks" in the shoulders. Because of how the tyre rolls over the road, the blocks can suffer heel and toe wear under certain operating conditions.
When a tyre rolls, the individual blocks in the tread are deformed.
On entry into the contact patch, the blocks are compressed. In exiting the contact patch, the blocks rub against the road surface and spring back to their original shape, resulting in higher abrasion where the lug tapers off.
This wear pattern is more likely to occur on non powered wheel positions.
If the tyre is driven in compliance with the specific operating conditions, the difference in height between the front and rear edges of the block does not exceed 0.8mm, a level at which no noticeable deterioration in the tyre's characteristics is to be expected. More conspicuous heel and toe wear points to specific operating conditions (improper inflation pressures, excessive toe in, driving style).
To arrive at an improvement in the tyre wear pattern and a relative reduction in road noise it is imperative that tyre pressures are maintained regularly in accordance with the manufacturers specification. Also rotating the wheels has the effect of evenly distributing wear, so that the tyre returns to its original favourable noise level after a certain distance.
Above all please remember that tyre wear is unavoidable as a frictional force must be present between the tyre and road surface.

Below is a photo that displays the condition of sword tooth and the condition that BMW’s suffer from, where the centre section gets worn away prematurely.

View attachment 14409

I don't, and haven't doubted a single word that you have written regarding this, but I still think this is poor.
I have owned many FWD cars, as most of us have I'm sure and none of them have recommended that I rotate the wheels twice a year (every 5000 miles) and I have as far as I am aware never suffered this condition.
Curiously in my half a century of driving I have never owned a VAG car. Never once a Volkswagen, Skoda, Audi, SEAT, Cupra, Lambo, Bentley or Porsche. This was not by intent but just how it was.

 

[Lovemyev]

I don't, and haven't doubted a single word that you have written regarding this, but I still think this is poor.
I have owned many FWD cars, as most of us have I'm sure and none of them have recommended that I rotate the wheels twice a year (every 5000 miles) and I have as far as I am aware never suffered this condition.
Curiously in my half a century of driving I have never owned a VAG car. Never once a Volkswagen, Skoda, Audi, SEAT, Cupra, Lambo, Bentley or Porsche. This was not by intent but just how it was.

Thank you for your support @Gomev.
Sorry that I bombard the thread with all of this what could be described, as info having no real relevance here I guess.
It maybe if some interest to somebody .
But it did turn my attention to my own ZS EV facelift that has now covered about 8,500 miles !.
Well probably due to a different type of suspension set up and the rear geometry of the car, I can say that it is NOT presently affect by the “Shark Tooth” phenomenon that plagues many of the VAG models.
ALL cars have their own different “Quirks / Weak Points” I think.
Some are like a fly buzzing around you head, just an annoyance, but others issues get under your skin to the point that you loose faith in the car and it’s life span with its present owner is cut short !.