Do not drive on that tire if you can avoid it! Seriously. That tire is about to delaminate. I have had that happen trice in my driving experience. Fortunately I didn't have an accident either time, but the tire significantly damaged my vehicles when it came apart. Both times it was the rear quarter panel.

I switched to Yokohama Advan Sport a/s tires. I liked the Michelin SS', but in the Midwest, they cracked. The yokohamas have been great.

AS/3's have a mileage warranty

Take them to a Michelin dealer and see what they can do on warranty. You will need proof of purchase

Treadlife Warranty: 6 Years / 45,000 Miles Half mileage for rear if different size than front

Workmanship & Materials Warranty:6 Years / Free replacement first year, 2/32" or 25% of wear, then prorated until 2/32" remaining depth

I had a set or rears go in around 12k miles and the replacements cost me only 30% of new price

Just got a new set of PS2s, they get my vote

I second taking them to a Michelin dealer to see what they can do for you. I have purchased a bunch of tires from Discount Tire Direct over the past few years including Michelins, and they have been good to work with. If you are budget conscious, they have a big Memorial Day sale that started yesterday. I check on a set of narrow body 18" tires yesterday, and you can get a set of Hankook V12 tires with a Y speed rating (186 mph) for $235 for a set of four, after rebates using their card. Figure on another $125 or so to get them mounted. They are a soft compound so they won't last as long, but I have purchased three sets for other vehicles in the past and I liked them.

turns out the production date of the RR tire (the second one in which the steel rib appears to be seen) was 4611, meaning the tire was already a year old when purchased in Nov 2012! By comparison the front tire was 3812.

JayG and Splitting Atoms: I will surely check into the warranty as the tires are under 5 yrs and 21,000 miles old. What does complicate things I guess is I bought them online at Tire Rack. I can try to return to them another Michelin dealer (there's a Discount Tire now in town).

Always good to check the dates on new tyres before they are mounted if possible.

I just bought new PS2s and the date was 4216 which wasn't great but then I realised that things can take while to get here by boat!

Call Michelin and they can send you to a local dealer
doesn't matter where they were originally purchased

Send a photo to TireRack. Their customer service is usually solid.

I have Sumi's on my 99 and 02. Did a rain-soaked DE in December in my 99 and was beyond impressed with the wet weather traction from those things. My instructor was impressed as well. That experience gave me the confidence to put them on my 02. Just did a mostly dry DE at COTA last weekend on those tires and came away impressed again.