[A4] Replacing a Partly Worn Tire?

[Jonathan]

Hi Stephen,

From a mechanical point of view, the difference in diametre of the tyre due to 
wear tred is negligiable compared to manufacturing tolerances, pressure 
difference, tyre temperature, fatigue in your suspension etc... So any drive 
train could handle a blad tyre on one side, and a brand new tyre on the other.

The only difference could be in grip, and that is only until the new tyre "beds 
in" assuming you replace with exactly the same tyre. Probably the wrong term, 
but I can't think of a better one. Bassicaly the new tyre will have to wear off 
oils and other rubish from manufacutre.

Having tyres cut can be extremly dangerous, and in your case, a waste of 
money.

I had a similar problem to you a few years ago, I changed tyre brand and tread 
pattern and rubber grade. This would leave a permenant mis-balance in grip, 
destabalising the car, so i replaced both front tyres. As I said before, if 
you replaced with the same tyre (or essentially the same) you'd be fine.

Cheers

Jon


> 
> Message: 1
> Date: Tue, 27 Apr 2010 16:41:42 -0700
> From: Stephen Kormilo <stephen at kormilo.ca>
> Subject: [A4] Replacing a Partly Worn Tire?
> To: quattro at audifans.com, A4 Mailing List <a4 at audifans.com>
> Message-ID: <4BD77636.5060908 at kormilo.ca>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> 
> Bummer. One of the tires on my 2002 A4 quattro received a sidewall
> puncture that cannot be repaired.
> 
> What is the group's advice re: replacing a single ~half-worn tire with a
> new one?  There is ~5/32" of tread depth left (~3/32" to the wear bars)
> on the tires, so I am not inclined to replace them all, especially at
> ~$240 each installed with all taxes. Will the difference in diameter
> between the new tire & the old ones cause driveline problems, or is the
> difference inconsequential? Are there any other factors that could cause
> problems?
> 
> The tires are Bridgestone Potenza RE960AS in 215/55x16 size, if that
> makes any difference.
> 
> Awaiting your wise words.
> 
> Stephen Kormilo
> Nanoose Bay, BC
> 
> 2002 Audi A4 3.0QM - Silver
> Departed:
> 1998.5 Audi A4 2.8 - Silver
> 1985 Mazda Rx7 GSL-SE - Black
> 
> email: stephen at kormilo.ca
>