I have about 12k miles on my Coopers and they look like new as well. I am very careful regarding hitting the curb, I tell my wife and kids , it’s not a contest who can get closest to the curb. I would probably change out these tires at 20k , would go with Michelin, not run flats. The reason for opting for the Michelins is purely based on name/ reputation. In reading the comments I am not sure if people are replacing their tires with run flats or not. I know that there are some very knowledgeable people posting here and I have heeded their advice. I too was disappointed when I was given the Cooper tires rather than the other brands MB was using. The dealer would not switch them out for me. The comments about the Cooper tires are somewhat harsh, perhaps rightfully so, I’ve had one repairable flat, no other issues.
For MB owners who have replaced their original equipment tires , please let me know if you ditched the run flats. BTW, I am just curious about turning in a leased vehicle, if the original tires were run flats, does MB require you to have run flats on the vehicle you turn in? I own my GLE, however, my daughter leases her MB. THANKS

 

Only vehicles with the 3rd row option and 19" or 20" tires have runflats, which I think is a small percentage. I have no proof, but I would think a leased vehicle would have to be returned with the original tire type.

 

It doesn't take a lot of high speed driving to overheat your tires. The car is over 5,000 lbs, and you're asking a lot of some 20" tires to do that work without overheating.
I overheated my fronts (21") pretty quickly in high temps (>100F) at the track (probably 5 miles before grip decreased) and as @Frenetic says, that looks like overheated rubber. It's a price one pays for pushing the limits, which is one reason I bought the 53.

For the moment, set your display to show tire temps along with pressure to get an idea of your operating conditions as you drive. It can help your diagnosis.

I thought my 20" Coopers were quite nice tires on my 2020 GLE450, generating more confidence with progressive breakaway, so I did push them to the limits on Mountain Twisties. They got Hot. I can't push tires with unpredictable feel as much, but I liked the Cooper handling better than others in that size.

Maybe you were having too much fun.

 

I've got Coopers on 20" rims, 11k miles. They don't look anything like that.
During a 8 hr drive down the East Coast in June, I saw temps of 100+ on the rear tires.
The highest temp was on the Drivers Front tire, by several degrees.
I assume that the turbo is on the driver's side and caused the higher temps I was seeing.

 

Post above-The sunny side of your vehicle will always run warmer given enough time in one direction.

Here’s a few of my thoughts, it’s easy to forget about tire pressure day to day:

Check your tire pressure after new car delivery and after Dealer Service. They tend to inflate to the Max pressure. In summer that can add to the higher pressure that follows summer heat.
If you live in a colder winter climate, don’t forget to check the pressure again in late spring. Personally I run a little higher pressure in winter than in Summer because of the large swings in temps in summer heat.
it’s a good idea to switch to the tire pressure screen periodically. A nail or screw will lose pressure slowly at first and the sooner you catch it the better for the tire.
Over time your tire will accumulate more moisture as air escapes and is replaced with new air containing moisture. Anyone with an air compressor knows about how that happens-although amplified with a compressor that exchanges a high volume of new air. Moisture results in more temperature fluctuation in the tire.
You can reduce temperature fluctuations a degree or two by running Nitrogen in your tires like they do on Aircraft that see huge swings in ambient temps. I normally blow $30-40 at Costco to have my tire air replaced with Nitrogen. Costco has free external nitrogen stations at most if not all stores if you want to top off occasionally. It gets your hands dirty and by then you have warmed up the tire so need to calculate the “warmed up” tire pressure. Costco uses 3 PSI, I usually check mine at the correct cold temp and then adjust for the new temp.. (PIA at times & there is a school of thought that Nitrogen has little value)
IMO, tire life and tire performance are better at proper temps. The tire is designed to handle some fluctuation in temps but like anything else there is a sweet spot that’s best.

 

That's not a very high tire temp. It's likely that your Driver's side was on the Sunny Side, which adds about 3 - 10 psi. The Turbo is on the right side, but shouldn't have an effect.
It's good to get a feel about how your temps are affected by different things.

 

A little history on Cooper - Nokian - Goodyear. FWIW.
Instead of building a U.S plant, Nokian "partnered" with Cooper to build their World-Leading Winter Tires, sharing their compound and other IP. So there was a period (late 'teens) that Nokians were built by Cooper for the N.A. Market.
But Nokian "suspected" or actually found that Cooper was using some of that IP in Cooper tires, so Nokian built their own factory in Dayton, starting production in 2019.
Góodyear completed purchase of Cooper Tire in June '21. Now Goodyear is producing tires with organic compounds very similar to the ones Nokian pioneered - Yucca, soy and other natural products that increasing wear and decrease heat buildup.
FWIW.

As an aside, Nokian is shuttering Finnish plants because of the Ukraine mess.

 

Not sure if it was mentioned but general rule of thumb is that tire pressure changes by one psi for every ten degrees in temp. In Maryland the largest swings are in spring or winter when get from below freezing to eighty degrees. Outside edge wear which starts as feathering is caused by under inflation of improper toe…or hard corners which is relative in a heavy car.

 

That looks like a bad batch of rubber. Definitely not normal wear.

 

For comparison with the OPs photo, here's a picture of my 21" front tire after abusing / overeating them at the track. Peak g load >1 braking, @1 in corners. Tire temp >200F.
Not the best use of an all season tire, but I have a better feel for its limits. That's important to me.

​​​​​

 

I believe Goodyear purchased Cooper.

 

The type of wear seen on Mikapen's tires is, in my opinion, very similar to what the OP is experiencing, except his is more severe. You don't necessarily have to be racing for tires to overheat and/or wear poorly. Bad alignment + under inflation + heavy loads/towing + hot environment/pavement/constant UV exposure + constant long distance driving/fast driving can all conspire to destroy tires, especially if you combine any of these together.

 

Oops my mistake. Thanks. Everything but the right players. Corrected.

 

I have a 2021 350 with 20 inch tires without a 3rd row and run flats were standard . As a matter of fact all the dealer inventory regardless 350, 450 etc. we’re equipped with run flats. The reason I know this is because my GLE had Cooper tires on it and I wanted to see if any identical or nearly identical vehicle came with another tire brand. There was nothing comparable in terms of equipment, so I purchased the vehicle with the Coopers. However I did notice they all had run flats regardless of the brand. Perhaps this is something regional , I live in NY. BTW, I would have preferred not having run flats.

 

UV exposure is only an issue if the tires aren't "exercised." Tires have Carbon Black, which migrates throughout the carcass, renewing the UV resistance as it's consumed by the UV. A static tire, such as an RV, doesn't get that migration, so the surface is eroded by UV.

Our tires are rated at 155mph, which is by definition, the max speed the tires can be driven for an extended period of time. Heat is the limiting factor, so "155" means they can shed heat up to that mph continuously without damage. They can be operated faster than rated, but only briefly.

To me. the OP's tires look like they've been overheated, but it also looks like a "bad batch of rubber" as mentioned above. It looks like there may be a warranty claim, although OEM's don't usually honor the tire warranty, since it's OE on the car.

In any case, I'd present it to the Service Department for solution.

 

Many thanks to everyone who has weighed in on this issue. Great advice given, as I do routinely monitor tire temperatures along with inflation values. After much consideration I believe there were three factors in play, 1- rubber compound is suspect, 2- harsh road conditions, potholes in general, 3- (might be the most relevant) was driving extensively on roads just repaired with “hot tar crack filler” that I believe compromised and overheated the tire edges. My theory follows: You may have seen those black ribbons of filler laid down by repair crews where you live. As I stated this condition appears to have occurred literally overnight. I actually felt that the repaired sections of the road caused the vehicle to wander as it “pulled” the rubber to itself. All during a NY heatwave for several weeks. My luck, I was one of the first vehicles to travel on the repaired section after the road was re-opened. My advice, avoid the ‘hot tar crack filled roads” if possible as it may destroy your tires. And btw I ditched the OEM Coopers and went with the Continentals LX25.

 

Did you go from run flats to non run flats?

 

I stayed with the non run flats. My OEMs were non RFTs and I have the space saver spare. I consider the conventional tires to have superior ride quality although I do like the convenience of RFTs to get to your destination without a tire change. I have OEM run flats on my x6, also happen to be Continentals.

 

As far as getting to your destination goes, RFT's and temporary spares have the same restrictions. 50 miles at 50mph.
Then there's the lower ability of finding a replacement RFT when you reach your destination.
The only real advantages are to manufacturers, who save weight and improve their CAFE.

 

Well, not having to change a tire on a freeway or side of a busy road could be an advantage, but degraded ride quality and cost make them non-starters for me.

 

I think run flats are made specifically for women. Imagine the ladies taking out those heavy wheels. When I was changing my wheels for winter in the C-class I asked my wife to try taking it out and putting it back and she did not even manage to get it off. She said "That is why I married you. I call you to change the tires". Previously on my ML I got a flat and I did the fix without taking out the wheel using those plugs. Took me like 15 minutes to find the nail, pull it out with pliers, then insert the plug and snap it off. It will be a different story if it is a blow-out then you will be forced to call for help without a dedicated spare. That only happened to me one time but it is on the c-class after hitting a pot hole in the middle of the night. Not sure on the GLE with it's huge sidewalls you will get a side blow-out but it can happen.

 

If the first two pictures (of the same tire) are a front tire, I'd say (from the uneven wear) the front end is out of alignment.

 

Best thing to do is get an alignment from the dealer before driving away in any new car.
Been doing that last 30 years when purchasing a car have dealer do an alignment (alignment is always off from factory) before driving away never had an issue with factory tires and they would last up to 30k miles and more.

 

Is a wheel alignment on a brand new car necessary? I’ve always felt that the alignment from the manufacturer is the most accurate. Personally I’ve never had an issue with a faulty wheel alignment on a brand new car. BTW, are you having them just check the alignment, are they charging you for this, thanks

 

They charge me for the wheel alignment separately 100 dollars. I don’t ask to check for alignment I just tell my S/A I want an alignment before I pick up car and he understands.
I’ve ordered my last 3 cars and all have been slightly off.