Tire identity-How do I tell if these are run flats or not?

Michelin tires designate run-flats by code: ZP, somewhere on the sidewall.

Ok, Ill check again.  Grazie!!!

Put a hole in them and see what happens. 

@Marty Grzynkowicz

Aside from my little bit of comedy in my last post, from what I researched those are not run flats. The XSE was a marketing designation as follows:

XSE, according to Michelin, is a technical breakthrough that allows company engineers to make tires with improvements in wet handling and rolling resistance, without sacrificing other performance characteristics such as wear, ride and noise.

And the MXV4:

MXV4 tires are Michelin's Grand Touring All-Season tires developed to meet the needs of coupes and sedans, as well as family minivans and crossover utility vehicles. Michelin Primacy MXV4 tires are designed to offer a quiet, comfortable ride, long tread life, responsive handling and all-season traction, including in light snow.

Is there a designation on the tire of:

"ILDGRTOAVWTTM"

(Italian Leather Driving Gloves Required To Operate A Vehicle With Theses Tires Mounted)

So my dilemma is this car is 13 years old and I cant tell how old the tires are.  Taking long road trip and trying to decide if I should buy new tires.  These have a ton of tread life left although they ride pretty hard.  The seller said they are run flats but I cant see that they are.  Hmmmmmmm.....

If the tires have a "ton of tread life left" and you don't mind the ride, there isn't any sign of rot or separation, they are inflated to the proper pressure and are holding air, the valve stems are in good shape and have caps, you aren't going off road with tires that aren't rated for it, why would you buy new tires?

Aesthetics?

You are starting to sound like an insurance agency owner who is risk averse.

The car is 13 years old, so, pretty good chance the tires aren't any older than the car. Look at the mileage on the car. Low mileage, maybe original, you can check online to see what was original equipment. 

Why not contact the mfgr, check their website, they may be able to discern age. 

As Robert M said, based on what you provided, they aren't run flats.

Are you going to go through some extended stretch of road in the middle of nowhere and there aren't tire stores? Pack up 4 rattle cans of Fix-A-Flat. Could you sell yourself some kind of trip insurance for this little soire?

Think of the drive as a GRAND DRIVING ADVENTURE ACROSS AMERICA!

Come on buddy, put on the gloves and go. If you get into the trip and hate the tires, buy new ones.

Post some pic of the car when you get a chance.

Thanks Dad,  that advice was  reassuring.   That's what I needed to hear.

I'm grabbing the gloves and I'm off in a few days

Good for you!

Have a blast and make good memories! 

Should be a nice respite from all the work you do.

There is a code on the sidewall that is the manufacturing date; a tire website will tell you what to look for and how to read it. And here it is- 

https://www.tirerack.com/tires...chpage.jsp?techid=11

This will tell you definitively how old the tire is. I've heard it said that anything over 6 years should be replaced; if they are over but close, still look great and pass Bob's inspection list then maybe, but if they're substantially older then it's time. Al

PS- I know it seems like just another expense, but tires really don't cost that much (especially our sizes) and it is a matter of safety. Choose wisely my friend...

All tires have a coded manf date stamped into them in this case 16 week of 2012

I've always been of the opinion that if tires are maintained properly and not allowed to have contact with the ground at one spot for too long that they will hold up for much longer than 6 years. That assumes they aren't eaten up by mileage that diminishes tread or sidewall damage, etc.

I thought that 6 year rule was the product of marketing, not engineering, but maybe I am mistaken.

Your experience may differ.

I recently swapped out Michelin LTX All Season tires on a Toyota 4Runner that were 9 years old but had perfectly good tread.  The tread rubber had hardened to the point where when driving in wet conditions the traction control kept activating.  Plus the side walls has numerous cracks and even cracks between the tread.  Much as I liked the ride and roundness of the Michelins I went with cheaper (1/2 the cost) Kumho Crugen.  Agree 6 years is probably too early (especially if tires are NOT exposed all the time to sun's rays) but 8 years seems justified to me. Heat build up on long, high speed trips should also be a concern.

New Summer performance rated tires seem to have a much shorter tread life so maybe the mileage/time are syching up.  Owners report the Bridgestone's tread on new Miatas are gone at 24k miles.

Wish I could get 9 years out of the All Terrain TA's on my 4Runner...

Jim Kelly posted:

Michelin tires designate run-flats by code: ZP, somewhere on the sidewall.

Jim.

I'm not sure about that ZP code on run flat sidewalls.  These are run flat tires off of my 2009 BMW and they show a ZR code.  Maybe the code has been changed since 2009.

By the way, they are for sale if anyone needs them.  $150 +shipping for the pair.  Thread is good, about 75% left on them.

 Thanks Greg,  these are 14 years old :-0.

Hi Troy,

It would be too easy if all tire manufacturers used the same code to identify all the various aspects and ratings on tires, eh?  Then the consumer could easily become a knowledgeable buyer, not a situation many manufacturers want.  Thus, each maker uses a different code.  Michelin and Tire Rack both state that Michelin uses "ZP" for zero pressure to signify their run flat tires, but they may have used different codes in the past.  It reminds me of the successful business plan of mushroom farmers in my neck of the woods: feed 'em BS and keep 'em in the dark.

Jim (as usual) makes a great point. fourteen years ago the run flat symbol may have been different.

So the car is thirteen years old and the tires are fourteen years old?

My hair is starting to hurt.

Robert M posted:

Put a hole in them and see what happens. 

You may be back to this.

New tires.

It's not marketing, it's science. UV, etc. (and years) age rubber. Moss did a test with New-Old Stock tires that had sat in a barn, wrapped in plastic for three decades. They were "brand new," but they were no good. 

Does it mean you'll die? Probably not. The Goodyear Eagle GTs on my Chevy II were 20 years old when I sold it, plenty tread left. And I'd run that car many miles over hot Florida roads during their second decade. I wish that I knew what I know now...

I think 6 years is fine. 10's probably OK. Maybe.

I wouldn't run 14-year-old tires again. 

Interesting article, Ed.

I don't know where the line is, but three decades is too long for me to trust them. I wouldn't have bothered going through a test. Sell them to a museum to put on a car that is never driven.

Remember, "Never trust anybody (anything) over thirty." circa 1965 hippie precept.

Keep in mind that tires degrade not just on the outside where it's visible, but moreso from the inside out. Oxidation rates are higher inside a tire due to the higher air pressures there. Heat (driving underinflated, living/driving in hot climates, etc) and lack of use (oils in the rubber don't circulate) also cause tires to age prematurely. These cause the rubber to harden and crack. As the cracks spread inside the tire, it'll eventually cause tread separation. Tire failures are going to primarily come from age, not mileage, and that's backed by NHTSA findings, so get those old tires replaced regardless of what they look like on the outside. Don't forget the spare, inflated spares don't last much longer than tires that get driven. 

Thanks everyone, I put on a fresh set of Michelin Pilot Sport a/s 3s.  Worked all day so I did not drive it,  but Sandy said they are awesome on the car.  

I had Michelin run flats on the BMW and they said, RFT on the sidewall.