I had these tires on our 95 855 wagon. After about 10K an

inspection showed 3 had sidewall damage. Little cresent

moon shapes pieces of rubber flapping on the sidewall at

the rim edge. All on the inside of the rim. Tire store I

took it to said they see this on BMWs too (Conti OEM on BMW).

They attributed it too pot hole damage and/or low air pressure.

I never let the tire pressure get too low but pot holes do

hit the tires pretty hard due to the very stiffer suspension

on the 850s.

I did bring this up in the past with a post on the topic and

it should be noted that nobody else reported similar damage

with this tire. So, my experience may be unique. I would still

have the tires inspected carefully pying attention to the rim

edge inside and outside of the tires.

I replaced them with Michilin Pilot H4s.

Hi Norman,

There are several ideas you can try but first make sure there are no kids in your neighborhood playing a bad joke on you by letting out some air once in a while. If you know for sure that some practical joke is not being play out at your expense you can try the following ideas:

Check to make sure that all air stem valves are screwed in tight. You can buy a stem valve tool at a local car part store for a few dollars. Also check the stem itself. This can be done by bending the stem and listen closely for an air leak (liquid soap will also work). I had a bad set of stems install several years ago. They were a little too small for the hole in the rim. If the stem valves and stems are all ok then try the following.

If you are a do it yourself type person get a large tub. Fill it with water. Remove each tire and set it in the tub and look for air bubbles. If you fine a bubble stream mark it with a bright color crayon. Or if you have a small tub place the tire in the tub edge on and rotate the tire until you have checked for air bubble streams. They will be easy to spot!

If you have found an air bubble take the tire to a tire center and get the leak fixed. Some tire centers will fix flats for free and some will find the air leak for a small charge. If you have to have the tire removed from the rim make sure to have the rims checked for flaws and imperfection. A slight warp in the rim can cause the tire lip not to seat correctly thus causing a slow leak. Hitting a big pothole at high speed can damage the rim and tire. If this is found to be true the rim can be repaired but you will have to buy a new set of tires. Volvo does not recommend the mixing of tire brands on V70XC. Rim leaks can be fixed by using rubber type glue on the rim lip and re-mounting the tire.

Good luck,

Steven---

I just installed a set on my 940T. The surface that comes in contact with the rim looks like it was made to accomodate a rim with a bigger flange. That is to say that I wondered if there was enough contact area at the interface. Perhaps you are experiencing what I was worried about, that the seel is not sufficient. This is the only thing I can think of to explain why all of them lose that much air, other than bad valve stems.

I don't know if the loss is occuring quickly enough for this to work, but you could try pouring dish soap or liquid bubble all over the tire/wheel interface to see if bubbles form.