Hello, I'm new here. I was driving on the freeway to meet up with a friend, I live in California btw. My tire malfunction light came on, and I saw my PSI rapidly go from 36 or 40? to 26 to 15 to 7 to 4... I pulled off at the next exit and pulled into a gas station. I immediately called mBrace and told them what happened. They confirmed I have run flat tires, I asked for a tow truck, they said since it's Thanksgiving, I wouldn't be able to get my car fixed until tomorrow which is fine. They stated since I have run flats, I can drive the car home under 50 mph up to 50 miles. I asked for a tow truck either way, they said that he would be able to tell if I can drive on them. Once the tow truck got there, he looked at my tire and said since it's a run flat and he couldn't find any nails or anything, he said that I should be able to drive home safely. He also felt around the tire to make sure it was intact. He also added air to the tire, but it immediately came out. I asked him again if he felt it was safe to drive home, and he said yes. So I started to head home, I was 21 miles away from home (if I take the freeway). I was driving about 20-25mph on side roads. I could hear the squishing sound of the tire, I called mBrace again and asked if that noise was normal, they said yes. I was about 5 miles from the location of the flat tire and I started to hear a thump thump sound, called mBrace again, they said the sound was normal, and that I could continue to drive, while they were on the phone, I pulled into another gas station, I told her the tire was completely flat now and my psi was 0. She said that I was fine, I was driving on the spare tire portion of the tire and that's why it was making the thump sound, she took my phone number down and said she'd check on me again to make sure I made it home ok. I was about 7 miles from the flat tire location at this point and the thump noise started to get louder and louder, my car was shaking hard with every thump and I called mBrace again. I asked them to listen to the noise and asked if it was normal, they said yes, and that I could drive all the way home. My car wouldn't stop rocking hard and they repeatedly told me it was safe, it's the nature of the run flat tire. I was driving between 10-20mph at this point. I finally said I couldn't stand the shaking and rocking of the car and the strong burnt rubber smell that started from when I first started driving. I pulled into a third gas station while they were on the phone and confirmed that my tire was completely shredded. They wanted me to trust them and continue driving. At that point they sent a tow truck and an uber for me and my 6 year old. We got home 4 hours later after the blow out.

Here's my question, I have a tire and wheel warranty on my car, did I void my warranty by driving on the run flat and having it shred? I was on the phone with mBrace while this was happening and they kept telling me I was safe to drive home. I'm now worried about my wheel, my obviously shredded tire, and any other possible damage from driving the car like that, (suspension, undercarriage??) I have an extended warranty too, but I trusted them and I kept pulling over and telling them what was going on, and now I'm scared and worried.

I attached some photos and a video of what it sounded like while I was driving, they said this sound was normal, this was before it started thumping really loud and rocking the car hard.

The other crazy thing is I was at the dealership yesterday complaining about a squealing sound that I've been hearing for a year (bought this car exactly a year ago, the service advisor kept telling me not to worry about the sound) when I back up and it started making a slight grinding sound too, they told me not to worry about that, and that my brakes and tires were good.

 

Just my opinion:

Your wheel looks 100% intact and fine. The RF performed as expected - it got you home. You need to get a new tire. FYI I had to replace my Pirelli P7 RF because of a bubble. Tire, mounting and balancing with sales tax was $348.

Happy Thanksgiving.

 

It didn't get us home, it only got me about 5 miles from where I had the flat and it was rocking my car like crazy by that point, I had to have the car towed and took an uber the rest of the 15 miles back home. The entire fiasco took 4 hours...

 

Obviously run/flats don’t always work out. No way of knowing if it would have actually gotten you home, noise and all. You chose the right course.

 

Meanwhile, if said vehicle had been equipped with a jack & spare—as EVERY passenger vehicle should be—the driver or Roadside Assistance could have changed the tire out in about 15 minutes and everyone would have lived happily ever after.

I hate run flat tires and swap them for traditional tires as soon as I get a new car. In my S560, I carry a compact spare, jack & tool kit. As a Boy Scout, I was taught to always be prepared.

 

You realize that not everyone wants to give up a substantial portion of their trunk for a spare. I travel a lot and need all the space I can in the trunk.

I understand once your RF wears out going with non RF: But swapping out perfectly good RF for non RF is literally throwing over $1,500 down the drain. A true boy scout would have both: RF and the spare: double protection.

Also, in the final analysis both you and the OP needed road side assistance: you to have your tire changed and OP to be towed.

As to having a spare: No question I agree with you 100%: Each car should have a spare and jack. However every manufacturer is taking weight out of their cars to improve their corporate EPA mileage. Removing the spare and jack saves between 30 and 50 lbs. Mercedes also thinks that we Boy Scouts who can and have actually have changed a tire are a dying breed. Although I have tried to teach them, neither my son, son in law, daughter and daughter in law has every changed a tire. If they get a flat, they call me first and then a road side assistance. Ditto for my wife!

BEV's are the same. No spare and not even RF which weigh more than non RF: they give you an inflator kit.

Everything is done to save weight.

Considering the demographics of the average Mercedes buyer, I suspect RF make more sense than an inflator kit.

PS: Just remembered that our 2018 Ford Edge Sport has a compact spare and jack buried under a cover in the rear so no trunk space is lost. Wish my E450 had one as well. I carry a very high quality inflator in the well of my trunk along with a tow rope!

 

My other car, an Acura MDX hybrid has non R/F and no spare, an inflater. I bought a spare tire kit, including a compact spare for $400. Cheap insurance. I’ll still call if it needs to be changed. I’ll have them change it.
When and if I keep the C300 long enough for new tires, I’ll probably still get run flats.

 

So I guess you think that I just take my brand new S Class down to the tire shop, have them put on the conventional tires of my choice, flip them my American Express Centurion Card and then deposit the run flats in the local landfill on my way home, right? Actually, on all my S Class sedans that I have had since they started using run flats, I negotiated the swap before signing on the dotted line. I’m sure the dealer installed the take-offs on CPO or other used vehicles.

After being a member here for many years, it still amazes me how some folks just have some sick need to try and humiliate or discredit other members. So often, they feel they’ve found a “GOTCHA” moment and post things that are just idiotic. Sheesh!

 

I had a couple of flats when I first got my '18 E300. I was able to drive to the MB dealer on one flat after trying to get a repair or replacement at 2 nearby tire centers. The tire centers refused to repair the flat and wanted to order a replacement tire (3 weeks). The dealer replaced the tire at no cost compliments of MBUSA on the same day, a Saturday. The second flat was so severe that it was not drivable. A flatbed truck was needed to get me to a MB dealer 3 miles away. (Still no available replacements other than at a MB dealer.) After that I ordered a spare wheel/tire from MB and purchased a jack and tools from Walmart. I often drive through Everglades National Park where I am more than 100 miles from from anything other than a questionable gas pump on the side of the road. (I carry a full Jerrycan for security.) If I need to use all of the trunk space, I put the spare in the left side passenger space. I drive with the seat all of the way back so the space cannot be used by a passenger anyway - zero legroom. I replaced the run flats with standard tires.

 

Not everyone on here has S class money. They may not be able to negotiate a swap of tires. I’m on the C forum and the BMW forum. Plenty of people go to a tire shop and pay to have them swapped out. I didn’t see any insult in the comments.

 

Was not trying to insult or demean you and if you felt I did, I apologize.

Honestly, I didn't know, before taking possession you could swap out the RF that came with your car for non RF.

In swapping, did you get money back from the dealer, or was it an even exchange or did you have to pay extra?

As I posted I have Pirelli Centurato P7 RF on my car.

From Tire Rack, the Cinturato P7 non run flats are $195: the Cinturato P7 RF $300 so there is quite a difference in the cost between non RF and RF.

see: https://www.tirerack.com/tires/TireS...erformance=ALL

 

Carrying a Jerrycan: shades of 1973 and the first Arab Oil Embargo! I remember doing that as well. Today my wife and kids would kill me if I did that!

I have driven "Alligator Alley" and you are correct: Not having a spare might be problematic. Is there cell service or dead zones?

FYI, here in NY area, twice when I had to replace my front tires because of bubble in the sidewall, my wait was less than 24 hours for a MOE Pirelli Cinturato P7 RF.: Saw tire store at 3 PM and replacement was there by 10 AM the next day.

 

one thing no one has mentioned. You had a major air loss. Possibly catastrophic. With non R/F tires, you may have crashed the car. At minimum, the wheel would have been toast.

 

The E300 does not have the range to drive from Clearwater to the Everglades National Park then meander along 9336 and the side roads to make it back to Naples to fill the tank. Driving slowly consumes twice the fuel of ordinary driving.

 

Moral of the story (besides that we are Boy Scouts at heart):

Have a spare. Options are good. Those little spares don't take up much room.

note: Do they sell emergency tire bags on Amazon?

 

He would have towed me to the dealership but they were closed. I didn't have a spare, but it might not be a bad idea to purchase an extra tire, I don't know if it would fit in my trunk space though.

 

Hmm, true... I don't even know what to do, I had a 6 year old kid with me, that would have been bad if I crashed, that makes me afraid to drive now knowing I have RFs.

 

As pointed out by ElvisFan above, it would seem that you had a catastrophic failure. From the picture it looks like the sidewall blew out - another reason why the tire did not hold air.

With the RF while the tire was destroyed, the wheel seems to be intact. If you did not have RF, not only would the tire and wheel have been destroyed, but it would have been extremely difficult to control your car.

IMO, in the event of a catastrophic failure, you are much better off with a RF than a non RF.

 

Have either of you had a blowout in a modern German car? Because none of that happens.

And manufacturers choice to use run flats is more about saving money than weight.

 

I’m sorry, it’s the opposite. The RFs probably kept the car from crashing.

 

I believe Elvis is correct: In a blowout you are much better off with a RF than a non RF:

Without RF, in a blowout the tire can fly off the wheel and you end up driving on the wheel. Controlling a car driving on a wheel is extremely dangerous.

With a RF, in a blowout, the tired remains on the wheel and you continue to drive. You are driving on the remains of the tire not the wheel.

see: https://www.edmunds.com/driving-tips...-a-primer.html

and No: RF are not used because they are cheaper: a RF often cost $100 a tire more than a comparable non run flat; RF are used to save weight: :

see: https://cars.usnews.com/cars-trucks/...-pros-and-cons

 

I see you are quoting Internet experts to support your argument. :eyeroll:

Have you ever watched a tire be mounted on a wheel? Tremendous force is involved. A tire does not “fly off the wheel” in a blowout. If you continue to drive on a deflated tire at speed, yes, it will disintegrate. So will a run flat, as the OP has demonstrated.

Run flat tires may cost consumers significantly more. Manufacturers buy more than 1-4 at a time. A fifth tire, wheel, jack, lug wrench, hardware to secure it all, etc. probably add up to a dozen manufacturer part numbers, and each model is different. That all adds up.

A run flat weighs about 5lbs more than a conventional tire…call it 20lbs. The difference between that and a space saver, jack, etc. is negligible, especially in a 4-5,000lb vehicle. I won’t get into the fact that the added weight of run flats is un-sprung.

More recently, that space previously used for spare tires is now where batteries go in hybrid and electric models. More range = more revenue. And more weight, not less.

Follow the money.

Again I will ask: Have you had a blowout in a modern German car? Because, again, none of that happens.

 

I had a catastrophic tire failure with run flats. I can't say it was a blow out, but the tire sidewall was destroyed. I didn't even have the opportunity to drive on the tire after the "event". IMO hurricane debris hit the sidewall and destroyed the tire.

 

I find it all strange and confusing. Why? is the main confusion. Is it to save the manufacturers cost, or some technical reason? The problem is whether or not it's right for most consumers. It may be right for some, but others?

Ride quality is another thing. But hey!, with all the low profile wagon wheels, who needs that? Maybe these companies figure ride quality isn't important any more simply because of that. I haven't even used RF for very long, but the idea of them is making me... not like them a lot.

 

That last line makes no sense.
All manufacturers use basically the same brands of tires. If an object is hit , it doesn’t matter if it’s a Mercedes or a Toyota. Except for the fact that the German car probably has lower profile tires, which are more prone to fail on potholes, etc. As OP mentioned, road side assistance told her to drive on it, instead of sending a truck. That saves money.