Tyre Noise

[maxaret]

Just been doing a partial pre winter service on the polo and whilst checking the brakes etc - I had a look at the tyres.
I had swapped the tyres round when I first bought the car as I always want the best tyres on the front - so I knew that the back tyres were close to replacement anyway.
Since we have had the polo it has tended to have a 'Woo Woo' noise similar to a wheel bearing noise when going faster than 30mph,I had not worried about it as a friend of mine also has a polo with an identical noise.
The car had  ended up with 2 Roadstone tyres on the front with 4mm remaining.
The 2 rear tyres had just less than 2mm remaining and I cannot remember what make they were LOL (cr@p make anyway).
After a little online lookin and then calling up to see what was in stock locally I ended up buying 2 Dunlop SP's (bluresponse) for a decent price (fitted to front) and it has transformed the handling of the car (even with the 2 roadstones on the back) - and also the Woo Woo noise seems to have gone - although we have not done any long journeys yet.
Its always easy to forget how cr@p tyres can affect road noise as well as the balance of the car

[Stef205]

tyre out of shape, rub your hand over the tyre you should feel high and low spots in the tread.

[maxaret]

Yes it was a bit Stef thanks - but gone now as tyre been replaced

[Ben]

Sounds like the 'saw tooth' wear. I have the problem with my mk5 golf gti. I just periodically swap my tyres around to even it out. Theres some info on it here, not that it matters now you've got new tyres!

http://www.pistonheads.com/gassing/topic.asp?t=1242766

Would still be worthwhile getting your geometry set up, from reading that thread the toe being out seems to have the worst effect.

[maxaret]

Thanks Ben
Yes the steering geometery is being done on tuesday,I also found a broken front spring so getting that changed on tuesday followed by the steering geo check.
Hopefully it was because it was a very cheap tyre - they were on the car when I bought it (I always buy decent tyres) - like you I change tyres around to get the most out of each tyre,I do not normally swap side to side or diagonal - I usually just put the worn tyres to the rear.
Interesting pistonheads article thanks

[Ben]

No problem, hope the alignment sorts it out for you

[Poodle]

Usually tyres going out of shape is caused by either really old and/or cheap tyres or by knackered suspension components - might be worth having a look at your bushes and balljoints.

[Jonny81191]

 I've seen a lot of new vehicles that just destroy tyres on the rear, running them out of shape before the tyres are even halfway worn.. Especially VAG and Ford stuff, we had a new passat cc in work a while back that had been to the main dealer several times because of the problem. Volkswagen's response was to track it up the first 3 times, attempt to charge for replacement shocks on the 10k service, then begrudgingly fit a free set of tyres before saying it was down to the customer driving too fast. At this point the car conveniently ran out of warranty.

I still can't work out what's causing the problem, obviously on some vehicles there's an underlying problem as poodle says. But look at any new repmobile or family bus with over 5k on it and no matter what brand of tyre is on there, I'd wager the inner edge on the rear is out of shape, or at least showing signs of it. If anyone knows the cause of that, I'd like to know. I struggle to believe that so many cars are being designed with such a flaw in the design, it's not a problem with older cars, or at least not as bad. So what's changed ? 

[Rippthrough]

Toe change from multilinks to make the handling safer and gain camber at the same time so the car progressively understeers. Hell on inner edges.