Cleaning my wheels today and see that my left front tire has 2 big bubbles in the sidewall. This will be my 3rd replaced tire in 4 months (blew two tires at once after a nasty pothole), what's up with these tires? Getting quite annoyed.

Continental tires unfortunately suck imho and are very prone to bubbles. I had to replace a ContiProContact on my W211 E550 after the winter and the tires were less than a year old. The Pirelli PZero Nero's my W212 came with seem to be holding up better than the Contis ever did.

that's funny because everyone has always said the cont's were good tires........
I've only had one flat so far.......since October........

are you considering changing brands?

I've never had a flat ever, nore a bubble. I only run Michelins though.

I have had Conti's on my prev BMW and Porsche and had no problems. Both my E's also have Conti's and so far I can't complain. I hope I am not the exception.

Have Contis on my current ML550 and my E. Had them on 4 prior MB's. Never had an issue other than one flat caused by a nail. Bubbles in the sidewall are called separations. Caused by either rubbing a curb or hitting an object or pot hole at some degree of speed. I think your problems are due to the pothole you hit and perhaps some other things that you have done maybe inadvertantly. Don't be quick to blame the tires. Too many of them out there with very few reports of issues like yours. The separations do not always show up right away. In any case get tem off of your car if they have bubbles in them

I have them on my BMW and MB too no issues.

To the OP, unless you ran them over huge potholes or stretching the tires, bubbling is a warranty issue and can be replaced

The first 2 times I messed a tire up i went new and paid 2 and change for a new tire. Then after that i figured out why spend 225ish for a tire that i am only going to break again and went the ebay route. You can get a tire with like 80% thread for like 65 bucks and spend 20 bucks to mount and balance the tire.

I always keep a tire in reserve in my office and when i break one i threw the reserve on and order a new one

The tire in question was replaced 2 months ago, when I blew the front and rear after hitting a pothole, by my dealer. I got my car in Nov so the tires were basically new. I called my dealer and it was covered under a road hazard warranty so got a new tire, just paid tax and mounting fee (Whew). When I blew 2 tires, they went flat within 2-3 blocks. I went back to take a picture of the pothole and other cars were hitting hard but did not get flats, at least not within the 3-5 blocks after hitting the pothole. With the new tire, I have been extremely careful as in 20 years of driving, this was the first time I got a flat from hitting a pothole, I may have hit a small pothole at low speed or driven though construction zones where the road is covered with metal plates but nothing severe. Between my wife and I, we are on our 5th Mercedes, and no tire problems before. With my E, the tires seem a little fragile.

I knew Conti ProContacts were trash as soon as my W212 E550 was delivered. Car spun out first time I nailed the throttle (from standing start, rotated 90 degrees, without any forward movement).

Many stories on line of ProContacts with premature failure.

I threw them out by 1k miles and replaced with Goodyear F1 Asymmetrics. Much improvement in dry and wet traction, quiet ride.

I had the dealer trade out Contis on my ML 350 at delivery, knowing this history. Michelin Tour HPs are great for MLs.

Good to know, will most likely switch out brands when the time comes.

ebay is best route 65 a tire and 20 to mount and balance

Which tires are you buying from ebay? Same Conti's? Just curious.

Continental conti pro contact 245 40 18 same that come stock on the car

Does anyone know the method as to how an E ends up with Pirelli's or Conti's?

It seems to random. I was so overjoyed when I noticed my car had P-Zero's, as I was expecting to be let down by the Conti's.

I've always thought that 'tire shine' crap accelerates the degrading of tires......

but no one will ever know that for sure

Probably does actually. You definitely DO NOT want to use Armor All in your interior, as it can lead to drying and cracking, so maybe the same goes for tires? I use Armor-All wipes on my tires, but got the "protective" stuff, over the "Supreme Shine" stuff, as I figure maybe it has less abrasive qualities, and gives a more sharp matte look, then "SUPER SHINE".

The last time I checked this is IMPOSSIBLE in a Mercedes, maybe you should take it to the dealer and have the esp checked.

From my experience, Conti's appear to be very prone to bubbling. I think Conti's sidewalls are a lot softer than a similar Michelin or Pirelli tire.

As for the tire dressing, I can say it does soften sidewalls and makes the tire more vulnerable to punctures and bubbling.

On one of the Volvo S80 forums they have many issues with the Pirelli P Zero Nero. It all boils down to this: The larger the wheel and lower the tire profile, the more vulnerable the wheel and tire is to road impacts. I think you could vist any number of forums for any number of cars, and you will see that the only common thing is the low profile large wheel combination.

One reason why I avoid low profile tires at all cost. They might look nice but I don't get the luxury in getting stranded on the road with a blow tire and the inconvenience and cost of having to have that tire and/or wheel replaced...

This is correct. I for one also avoid low profile tires. Thats too much compromise and potential grief just for appearances sake and I dont even care for the appearance. In addition the ride is harsher and the handling is poorer.

One of the car magazines did a comparison of wheels and tire sizes. They used a Golf IIRC. The "sweet spot" was right at 17" for performance and comfort. There was very little improvement in handling above 17" but there was a noticble hit to acceleration between 17" and 19." Essentially the point was that anything abouve 17" on a given vehicle is all about cosmetics.

I believe that if it has petroleum as an ingredient it can damage and crack the tires.

It is my turn today, finally. I hit a pathole early morning in the dark. Then few sec later, the TPMS warning went off and my right rear tire pressure went down. I managed to exit the freeway and stopped at Starbucks.

I saw 1/2" slice towards the side of the tire. Called MB Roadaside assistence. When removing the tire, the guy dropped the wheel on top of the wheel nuts..faced down ...... It caused several big chips..

He got nervous and drop his android phone over standing water and his phone went off right away...What a bad day this morning...

So I went to Discount tire and get the new tire mounted ($250.00). The Dealer will fix the wheel tomorrow.

I hope I don't have to do this often. I bought lottery today.. see if it meant something.