Tires: Run flat tire, runflat tires, inflation pressure

Question
Hello. Very short and easy question - Can it be repaired. I read different opinions on different blogs.
The tire is Good Year LS 245/50R18. Made 22,000 miles. Back left tire.
And if it has to be replaced - can I replace one, or two, or all four (its all wheel drive)
Thank you.

Jay

Answer
Jay,

Here's the deal:  In normal tires, you can see the damage to the sidewall due to being operated without inflation pressure.  But in RunFlat tires, that damage is covered by the sidewall insert - the thing that makes the thing work.  Because you can't see the damage, you can't assess if the tire is beyond repair.

So many tire manufacturers take the conservative approach and say you shouldn't try to repair these tires.  Others take a more risky approach and say you can - knowing that the odds of something bad happening are low.

- BUT - there is a real risk, because a blowout at high speeds can cause a severe accident.

So I can understand all points of view.  If I were a tire shop, I would do repairs to RunFlat tires IF I got the correct answers to certain questions - and the questions would involve how far the tire was driven on, and how flat it was.  Otherwise I would refuse to repair it.

Replacing tires on an AWD?  The safe bet is to replace all 4.  However, if the tires are within 2/32nds of an inch of each other, then you don't have to.  Also, if the vehicle is tolerant of differences in diameter, then you don't have to either (That ought to be in the owners manual.)