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Instead of adding one more complaint to the old thread, I hope this new one will start a discussion about the causes and solutions.

I traded in my '02 330xi for an '06 with Bridgestone RFT a week ago and then came across a lot of complaints on the web about this tire. Nobody seemed to have given any explanation, not BMW, not Bridgestone. If we don't know what caused it, then we can't prevent it.  Some loyal BMW owners are even jumping ship to other cars. It sounds scary enough that I did some search online to better understand the new technology, which may lead us to the cause behind the wide spread complaint and how we may be able to deal with it..

First, I found two very nice articles about run-flat tires (RFT) and tire pressure monitoring system (TPMS) that I highly recommend to everyone. See
http://www.edmunds.com/ownership/tires/articles/117588/article.html
http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=44

Based on the information in these articles, it seems at least plausible that many RFT owners have unknowingly ran the tires under low pressure for an extended period. That would explain premature tire wear and failure for many, but not for all. Unlike conventional tires, RFT have stiff sidewalls that make a flat tire stay more round, hence harder to detect by eye. The low profile tires on BMW make it even harder to see bcs the space between the rim and the ground is small to begin with. Many of us are under the impression that TPMS is safeguard that replaces our eyeballs, but this is often not true.

Having read the manual of the '06 330xi, I see that it uses a so-called "indirect" TPMS which doesn't actually check the pressure, it just detects the difference in rotation among the tires. This system would pick up low pressure in a single tire, but not seasonal pressure changes (due to temperature drops in the fall and winter) that affect all 4 tires. This would explain why many owners had to replace the entire set of tires early.

Another subtle point is that the TPMS had to be "initialized" right after the tires are inflated to the correct pressures, because that's the reference point used by the computer to compare the tire rotation later. If the system is not initialized properly, e.g., not reset after tire rotation or a flat repair, that would also end up running the tires at the wrong pressure.

The marketing pitch of these new technologies lead us to think that we would have less to worry: TPMS tells us when there is a problem, and we can keep driving 50 miles when the warning comes on. The truth, I think, is just the opposite: the new technology actually requires us to pay more careful attention to the tires than we're used to. A nail puncture in RFT can be repaired in principle, but apparently most service stations would not want to earn that $20 to risk being blamed for bigger problems later. The flat tire may let us go 50 miles to find a mechanic, but what good is that if he doesn't want to patch the leak? A tire store would only want to sell us a new tire for $200+, if they happen to carry the same brand/size we need. This is entirely understandable because it is reasonable to assume that some internal damage or weakening have taken place after a flat tire is driven 50 miles. Nobody can look at the tire and tell you that it’s safe to keep using it. BMW dealers would always have the right tire in stock, but the price is expected to be 50-100% higher than a discount tire store. What can we do to avoid this problem?

I can think of two precautions that we can take:

(1) Carry a pressure guage and a small tire pump in the trunk at all times. In my '06 330xi, a small well under the trunk floor fits my tire pump perfectly. When the tire pressure warning comes on, don't keep driving on the flat if you can avoid it. Stop the car at a safe spot, pump up the flat, re-initialize the TPMS, and then drive to find a service station. If you get there before the warning comes on again, chances are that the tire has not been ruined and the tire can be repired. Most nail punctures are slow leaks. If you have not driven on the flat, no damage has been done and you shouldn’t have to replace it. If it is a big leak such that the tire cannot hold pressure at all, I would still call a tow truck instead of driving on the flat. The truck always comes from a nearby service station that knows how to repair a tire. If they know you have not driven on the flat, they would be more willing to repair it. The expense of the tow is likely to be much less than a new RFT tire. If you’re member of an auto club such as AAA, the tow is free. A small tire pump should probably come as standard safety equipment on the car now that we don't even get a jack or an emergency spare anymore.

(2) Check tire pressure on RFT more diligently than with non-RFT tires, bcs our eyes cannot detect low pressure well. Do not let the TPMS fool us into having a false sense of security and check the tires less frequently. This is probably an important factor behind a lot of unhappiness about RFT, Bridgestone or not. Ideally, car makers will want to switch to using "direct" TPMS in the future such that the pressure on all 4 tires are checked electronically and displayed on the dash board by pushing a button. Until then, this new technology really requires more careful attention from owners, not less.

Would the above precaution work? Well, this is my true story…

I took delivery of my car on Friday, checked all the tires Saturday morning and they were all fine. When I went out to dinner later that day, the TPMS warning light came on after driving about 1 mile! I drove another mile to the restaurant; found that the pressure in one tire was ALL gone! I pumped up the tire, didn’t see or hear any obvious leak, so I drove home. The pressure has now held up for almost 24 hours, not sure what caused the leak. The warning light on the dash didn’t go away after the flat tire was reinflated. I read the manual and learned that it had to be re-initialized after each alert. I'll continue to monitor in the coming days, certainly won't take the car on a long trip. If I had not done my homework to learn about RFT and TPMS beforehand, I would be in a panic mode right now!  

There are a couple of other items that might be of interest:

Wheel alignment is the driving force behind tire wear.  Tires like to be straight up and pointed straight ahead.

However, vehicles like a bit of toe in.  It makes the vehicle feel more stable.  Many vehicles have fairly wide tolerances - more than what the tire likes - and the result is uneven wear.

Plus, it is possible to get more cornering capability by using more negatiove camber (the wheel is tilted inwards at the top).  BMW has been using this techinique for a long time.

The combination of toe in and negative camber results in shoulder wear on the inside shoulder.

RunFlat Tires have incredibly stiff sidewalls and don't react as strongly to camber.  The net result is that these tires are more likely to wear unevenly when subjected to camber.

I would suggest that anyone who experiences this type of wear (and the noise that comes along with it) get the actual alignment settings.  This data could be valuable in defining what the real tolerance should be.  

Here's my story. I have a 2006 325i and it has the run flat tires. It is making very excessive road noise and the handling has become unreliable over rough or wet surfaces. The car has less than 20,000 miles and we noticed the noise before ten thousand miles. When I asked the dealer about it they said run flat tires wear easily and we should monitor the tire pressure closely.  I did and I even purchased a digital tire gauge and compressor so I could maintain consistent tire pressure. The noise continued to get worse and when I asked the dealer again about it they said BMW was aware of the problem and if we would have complained before the car had 10,000 miles BMW would have paid for replacing the tires. We were not told there was a program in place to replace the tires the first time we asked the dealer about it. Now the dealer says BMW will pay for half of the tire replacement if we have less than 20,000 miles on the car. From what I've read on this forum and others many people are very dissatisfied with the run flat tires. They report cupping tire wear and excessive noise just as I have. They also state they are dissatisfied with the level of customer service they are receiving because BMW dealerships will not replace the prematurely worn tires. I have read several forum entries that talk of a class action law suite against BMW.  If you've had similar problems please post what the dealers are saying and what your experience has been in trying to get replacement tires.  

If you have proof of reporting the noise before 10K miles, e.g, in one of the service orders, some dealers would honor that and replace all 4 tires even if your current mileage is over 10K. They may also contact BMW to get authorization. I think BMW is footing the bill, but different dealerships may handle these cases differently. Even if they would only do 2, it's better than none. Some dealers offered the other two tires at cost. If not, you can always go elsewhere to get the other 2 done at a more reasonable price. Continental seems to get less less complaints and they are less expensive than the OEM Bridgestone EL42-RFT. I asked the local Town Fair Tire store and they told me that they could get the Conti overnight and costs about $200. Tirerack.com carries it for about $150 + shipping/mounting/balance. Getting 20K miles out of the Bridgestone is not so bad as it has a relatively low rating on wear compared to others. There has been some talk about the Bridgestone having a new modified version, but it's unclear if that's actually true.  

This is a follow-up of my original post, where I had reported the tire going completely flat in a few hours and then held the pressure for more than a day later. I brought it to Town Fair Tire for an inspection. They took the tire off the wheel, smooth the rim and remounted it. I was told that there was a bit of corrosion and roughness on the rim. This makes sense to me as the leak may vary depending on whether the rough spot is close to the ground when the car is parked.

This is also a good example why we should avoid driving on the run-flat tire with the warning light is on. In my case, there was no problem with the tire and it could be used after the rim problem was corrected. Had I not pumped up the tire before driving to the tire store, I might have caused some internal damage to the tire that would lead to premature failure later on. Any car with run-flats should really have a tire pump in the trunk at all times.  

Negative camber with to much toe out wears the inside edge of the tire. Get the car aligned. TPMS tells you when to pull over and fix your flat or run it flat and replace it. If you reset your TPMS it wont be active for a while as it relearns strategy in which time the tire pressure could be going down. Plugs allow you to patch a nail hole along side the road. Rotate your tires every other oil change and you wont have the shoulder wear on the front tires and the cupping on the rear tires.  

I will add, I replaced only one tire when I had a flat and because the FTM system does indeed monitor tire rotation, the difference in the tread was enough to cause the FTM system to continue to set off, even though I had re-initialized the system after putting the new tire on.  So, back I went to the dealer, replaced it's sister tire (I had to replace one tire because it had been knocked out of alignment and I hadn't noticed-I ran the tire worn).  As soon as I replaced the second tire, and re-initialized it, my car was all happy again.  

i am so sick of run flat tires

i have a 2007 bmw 328i and i've had many tire problems. They go bad quickly and very expensive, honestly i dont see what the benefit is in them.  You have to keep monitoring the pressure and theres no fixing them, you have to buy a new one.

Overall, never again will i buy runflat, neither will i buy or lease a bmw.  I love the cars but i hate how sensitive they are and living in LA, with our crappy roads and pavements, you will be very annoyed in driving a BMW.  





so i have a question, i have 6 months left on my lease and i just want to buy a USED run flat tire. can you guys help me find a place??


Thanks