I was on the freeway,running about 75 in the car pool lane when I heard a loud bang from the rear of the car. I thought something hit me.

I drove for another couple of mils when I noticed a message on the DIC (?). "55 mph maximum speed" then "reduced handling", them "Right rear tire flat".

I let off the gas and proceded to the right lane. locked the cruise at 55 behind the trucks and hoped this "runflat" thing was all it was supposed to be.

I was on the way to an appointment at the detailers to get the car done. The tire shop was two blocks from them, so I drove on.

I drove about 25 miles, Santa Clarita to Burbank.

I have to say that if it had not been for the display, I would not have known I had a flat. I was very impressed.

Got to the tire shop and the tires had to be ordered, so we did, and I then drove to the detail shop, had the car done, drove back and did the tires.

I have the Michlien zero pressures. When the original Goodyears were almost gone, I read the forum a lot trying to drcidr what to get. I wanted a better ride and seriously reduced road noise. In the end I decided to stick with a run flat, and yesterday that decision paid off.

I have a question for others running the Michliens. I am wearing the rears out in about 26,000. It wears the centers out down to the cords, while the rest of the tread is only abour 50% gone. I have been thru two sets of rears that have done this. Third pair went on yesterday. If you just look at the outside part when walking by, it looks like they are great. but get doen and look at that center strip about 1" wide, and it is gone.

Fronts have 50,000 and have about another 5000 left. They seem to be wearing evenly.

I run less that 30 lbs, sometimes getting the low tire pressure readout on cold mornings (24 lbs) The tires look like they have been run over inflated, but that is not the case. Car is an A4 with 2.73s, so it won't even burn the tires if you try.

My tire guy is going to have the <ichlien rep come out and look at them.

Anyone else have this happen?

Jay

 

Glad to hear the runflat looked after you. Impressive

I had a similar situation although not as dramatic. I damaged the valve neck when I was topping up the front left. It was one of those angled tire inflators and I twisted it as I pulled it off. It sheared the neck but not enough to break it at first. Over the course of the day it slowly deflated so when I climbed in to go home it was down by about 8 psi. During the ride it slowly lost pressure until the low pressure warning came on. By then I was only 5 miles from home but I climbed out to take a look. I pulled the cap off to see if it was a valve core problem and the whole neck of the TPS valve came off. All the remaining air came out in one go. I drove the few miles home at about 50 and as you say, I'd have been hard pressed to notice other than the DIC message. I live way out in the boonies so I'd have been looking at a flat bed home otherwise.

On the wear, mine have done 14k miles now. The wear is even and the front and rears seem to be wearing at the same rate. I tend to run them at about 28 on the DIC but it underreads slightly so I'm close to 30 cold. After what you say I'll get a tread depth gauge on them and I'll post up if I see any variations. Mine look good so far and I'd say I still have about half tread left so 25-30k seems about right.

 

Glad to hear you are OK

 

Nice that the tires did what they were supposed to do and got you safely to a repair shop.

 

I have the same tires as you and the rear are wearing the same. I run 30 PSI cold. So if the rep looks at your tires I would be interested in what he/she says.

 

What caused the tire to fail?

 

Are you trusting the dic, or are you checking the pressure yourself?
Something is definitely not right here. I'll be interested to see what the rep says.
Good luck.

 

Read the tire pressures with an ACCURATE gage! Compare that reading to the DIC TPS reading. Are your tire widths the stock OEM size on OEM rims?

I run 25-26 PSI cold in my 02 ZO6. I have wider rims ( CCW 505A's) with 305-30-19" on them. At 26 PSI cold, I get almost perfect even tire wear. Of course, mine are NOT run flats. That could maks a difference.

BC

 

I just replaced the GY Run Flats with Michelin Pilot A/S ZPs, on my '00 A4 / 2.73 as well, so I am very interested in comments regarding best air pressure to maximise tire mileage. I wore the middle out of my rear GY EMTs and the inside edge of the fronts.

I'm beginning to be convinced that 30lbs. cold is just too much for the rears, while it may be good for the fronts.........interested in actual experience of other forum members in this regard on run flat tires.

 

Several people have said that Michelin Run Flats wear down the center due to the softer "all season" rubber. I have heard that they run less pressure than 30 psi.

I run 26-28 psi on my Goodyear OEM Runflats to get even wear.

 

how are they compared to the Good years? do they ride more comfortably and perform better? my car came with an almost new set of non-run flat tires. I have plenty of life left in them, but some day they will need to be replaced. I'm seriously considering going with run-flats for the extra insurance they provide. but I don't want the GY's based on what I've heard.

 

It is night and day difference with what you noted above. Michelin A/S ZPs provide a much more superior ride and handling I think.

Good to hear they did what they are designed to do.

I can't comment on wear as I've only got about 10K on the current set, except that for now at 10K they still look new.

I run the pressure cold as stated on the door. It usually matches up with the monitor on the DIC within a mile or two of departure. I use a gauge that seems fairly accurate.

 

I would like to know too..

Rick

 

How old were the AS ZP's?

I have read a few posts (elsewhere) that are indicating these tires, in HOT climates, have a tendency to fail ~4-5 years.

Most indicated the same issue you describe - wear on the center portion, and that is where the failure(s) were occurring most.

Without exception the owners were running correct (~30) lbs pressure - as RECOMMENDED by both Corvette AND Michelin.

In all cases posted the owners had between 25k and 40k on these tires, and in no (reported) cases did Michelin assist with replacement - looking forward to seeing if that is different for you.

 

Seems like if you ride on the cords you will have blow outs.

 

I have 295/35R19 non-run flat Michelin PS's on the rear of mine and they are worn in the middle too as you describe. they were almost on the wear indicators when I bought the car and I have been running 28psi cold but they seem to still be wearing the middle more. Probably a characteristic of the PS series of rubber.

Peter

 

woops...see my next post

 

Have to love the run flats for that reason only....now if they only hooked up, they would be kick ***.......No clue on what tires to buy next.....still seeing what everyone else thinks about the same ones your asking about

 

30-31 psi HOT..that means adjusting and experimenting with cold pressure until you get 30-31 psi HOT. NASCAR racers are constantly adjusting pressures depending on conditions to get the best tire contact with the surface.

The 30 cold recommendation on the door is generic...they can't put an exact pressure because of all of the variables that people encounter...ie(road surface temperature,etc)
In the summer if you put 30 cold then drive on the highway for a period of time and the air temp is 90+, the tires can heat up to 36 or more psi and that is not a good thing. Thats why you should adjust the cold pressure so that when the tires heat up it should be in the 30-31 psi range. It takes some experimenting...I keep adjusting with the seasons>>>winter/summer<<<...but always adjust so it reads 30-31 psi hot.

And it has worked for me ever since


BTW...I got all this info from Evil-Twin
(For those who didn't get the honor of knowing him here on the forum...he is the retired GM engineer who unfortunately left the forum a while back )...lots of his info helped thousands of us here for years

 

Using the hot pressure is best. But 28 psi cold typically gives me around 30psi hot and they've still been visibly wearing more in the middle.

I have no idea what the previous owner did pressure wise though but they were around 30 or more cold when I drove it home so most of the wear may be due to high pressure. I'm just saying I dropped the pressure to try to even out the wear but it doesn't seem to be helping too much.

Peter