I have a nail in my Michelin 4S..Tire Rack Warranty claim adjuster said they recommend replacing the tire.
Warranty covers cost of new tire. Does not cover shipping, taxes and installation.

Why would I not just patch it? They cover that.

 

They don't want to insure a tire with a repair due to inconsistent quality of tire repairs in general. On a Y speed rated tire it's more economical for them to eat the cost of a tire vs the cost/liability of a potential blow out at high speed.

 

In an Audi owners manual, they claim that the speed rating cannot be maintained (is that the word?) if you repair a tire.

I would agree with that caution.


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That said, tire shops won't repair tires with a puncture in the sidewall. Knowing that, on my AWD daily driver, meant that I would need to replace at least TWO tires when I suffered a screw puncture in our car. Since that vehicle never saw large cornering G's or high speeds, I re-sealed the screw myself and left it in!!! Lasted another 20K miles tho' it did need to be topped-up with air occasionally. :

 

Makes sense, thanks.

 

I'd replace it if they're covering the tire cost.

 

Tire rack replaced one on my wife's XJR, and the Les Schwab store mounted and balanced it for free. They have continued to rotate and balance all corners, again gratis. Hope you have a Schwab (or equivalent) near you, yet as you've learned, it's best to replace it.