Cracked Alloys, time for manufacturers to publish failure rates?

[Scott7119]

This story is not unique. I have a 2017 Mercedes E220 Estate AMG foolishly I opted for 20-inch Alloys and run-flat tyres with a low profile. You can guess the rest, slow leaks, uncovered cracks in alloys, subsequent repairs, further failures, replaced alloys, all this whilst never driving over what could be described as a pothole. 2 years later front and back alloys have been replaced at a cost of over £3,500. I raised this directly with Mercedes as Sytner immediately denied any claim under warranty and that my issue was down to wear and tear. I asked Mercedes whether they kept statistics of the failure rate of Alloy and Tyre combinations, for safety reasons I assumed that they would, to track and improve performance, holding subcontractors and partners to account etc. Mercedes said that this information was not available to its customers and they were not obliged to release it. Which I find incredulous. It is evident on the forums, through conversations with numerous tyre fitting companies that certain combinations of Alloys and Tyres are not fit for purpose and indeed in some cases dangerous as tyres slowly deflate while carrying multiple fractures. My contention is that manufacturers are aware of the risks, 1) the additional running costs to their consumers when selecting options 2) the associated dangers of complete wheel failure. The consequences to consumers are significant maybe 20% or higher in terms of cost of ownership. In not disclosing this information are there measures of recourse under consumer protection? If Mercedes know that certain wheel and tyre combination has a 500% - 1000% percentage than another you would think they would be obliged to inform the consumer so they can make an informed choice. In saying nothing manufacturers like Mercedes imply equivalence which they know to be false and is then by extension misleading.

 

[Blobcat]

You said it yourself, you opted for wheels and tyres that aren't suitable for the road conditions we have. I can't see how the manufacturer can be responsible for the damage as they don't know how or where you're going to be driving it.

Manufacturers are in the business of selling cars, the fashion for huge rims with rubber bands on the outside is great for them (and tyre manufacturers) as it keeps the money rolling in. I've never understood it personally as I find it challenging to see my alloys when sat in the driving seat. When it comes down to it I didn't buy any of my cars for their looks alone (no matter how nice they are) I buy them primarily because they're very very nice to drive (and you don't get that with huge rims and no sidewall)...

 

[Gazwould]

This trend is bonkers , usually coupled with high maintenance diamond cut curb magnets , even on suv that used to have forgiving fat profile tyres .

 

[Wighty]

I must admit , both my cars are 17" summers with 16" winter wheels . I have only once had 18" wheels on a mondeo .
I've never cracked an alloy on those sizes (probably unlikely to ?) , but I've heard so many horror stories from large alloy/low profile tyres I just avoid them .
I would buy a car with them on but I would look to change them down to a smaller size asap .

 

[LostKiwi]

I run 19s on two of our cars with 35 profile tyres and have had no failures to date. I also run 17s on a third with 45 profile tyres and again no failures though I did need rims straightening.
On my Smart I run 16s with 40 profiles and again no failures though one is bent.

 

[Scott7119]

You said it yourself, you opted for wheels and tyres that aren't suitable for the road conditions we have. I can't see how the manufacturer can be responsible for the damage as they don't know how or where you're going to be driving it.

Manufacturers are in the business of selling cars, the fashion for huge rims with rubber bands on the outside is great for them (and tyre manufacturers) as it keeps the money rolling in. I've never understood it personally as I find it challenging to see my alloys when sat in the driving seat. When it comes down to it I didn't buy any of my cars for their looks alone (no matter how nice they are) I buy them primarily because they're very very nice to drive (and you don't get that with huge rims and no sidewall)...

I opted for a car in the showroom the wheels and tyres being 8 of 100,000 parts comprising a vehicle. I didn't know the wheels were not fit for purpose, I found that after running the car. The manufacturer will have known and they didn't disclose this. Engines have different performance as do wheels and tyres, engine metrics are disclosed as they have a consequence on the cost to run a vehicle. The cost to replace wheels and tyres is material over the lifetime of ownership. I've never had to replace an alloy wheel in 30 years of driving in the past 12 months I replaced 4 alloys and 6 tyres. I have learnt that rims and rubber bands as you describe them are indeed a bad marriage, Mercedes i suspect did know yet chooses not to disclose this which i believe to be wrong. The question was, should the manufacturers be forced to publish the information so customers can make informed choices.

 

[Blobcat]

I opted for a car in the showroom the wheels and tyres being 8 of 100,000 parts comprising a vehicle. I didn't know the wheels were not fit for purpose, I found that after running the car. The manufacturer will have known and they didn't disclose this. Engines have different performance as do wheels and tyres, engine metrics are disclosed as they have a consequence on the cost to run a vehicle. The cost to replace wheels and tyres is material over the lifetime of ownership. I've never had to replace an alloy wheel in 30 years of driving in the past 12 months I replaced 4 alloys and 6 tyres. I have learnt that rims and rubber bands as you describe them are indeed a bad marriage, Mercedes i suspect did know yet chooses not to disclose this which i believe to be wrong. The question was, should the manufacturers be forced to publish the information so customers can make informed choices.

Peter Wheeler of TVR fame used to say he'd spend hundreds of thousands of pounds designing the suspension system for excellent handling only for the owners to spend £5,000 and completely ruin it by fitting big wheels.

The wheels are fit for purpose, just not the one that you have put your car to but as I said, Mercedes don't know where or how the car will be driven. Mercedes want to sell cars and the current fashion is for large wheels so they fit them to certain cars.

As an example if you buy an SE spec E Class (basic one) you get real leather seats and 17" wheels, if you spend ££££ extra for the "AMG Line" you get plastic seats and also silly wheels. Mercedes are providing exactly what they're customers are wanting.

My first E had 18" AMG alloys fitted, I had them changed to the Standard Avantguarde 16" rims and had a comfortable ride and never cracked a wheel.

 

[John Laidlaw]

I’m refraining from comment on this subject entirely due to superstition....

 

[Craiglxviii]

The carmakers aren’t obliged to release warranty failure rates. Why would they be? They’re obliged to support warranty failures for those cars under warranty, thus it follows that the failure rate must be low enough to be affordable. That usually means something like below 0.02% failure rate of serial production.

A car usually has 2000-2500 parts to it, not 100,000.

The choice of wheels and tyres was up to you and so the onus on researching the choice was up to you. It should be fairly obvious that larger rims will give a harsher ride than smaller ones, and runflats even more so in combination.

By the way, the wheel and tyre combinations are demonstrably fit for purpose, they have to meet Regulation 124 in order to be approved for use. They might not have been fit for the purpose that you subjected them to however.

 

[LostKiwi]

Regulation 124 can be seen here:
https://www.interregs.com/catalogue/details/ece-124/regulation-no-124-00/wheels-passenger-cars/

A common cause of cracked wheels is driving over speed humps too fast, straddling cushion humps (puts excessive pressure on the inner edge of the rim which is the weakest part), pot holes and driving over kerbs.
Very rarely is it a design failure of the rim (though some rims are known to be soft and have as much resistance to bending as cheese - Smart Roadster Brabus rims being a prime example).

The bigger the wheel and lower profile the tyre the greater the risk of damage.

Defenders came with 16" wheels shod with 85 profile tyres for a very good reason.

 

[malcolm E53 AMG]

Traffic calming measures and potholes are generally to blame but we have another part to the equation namely runflats tyres which Mercedes seem to have recently adopted which in my opinion are as much to blame. BMW have been using runflats for some time now and have no doubt made alterations to the way in which their alloy wheels are designed to accommodate the extra stress created on the weaker inner part of the rim - I suspect MB still have this to discover

 

[Taffy7hfa]

Big wheels/low profile tyres are a fashion statement that's all, they're not necessary to make a road car handle well
and are not practical on our dreadful roads, you wouldn't wear your best shoes to walk across a building site would you ?

 

[LostKiwi]

Big wheels/low profile tyres are a fashion statement that's all, they're not necessary to make a road car handle well
and are not practical on our dreadful roads, you wouldn't wear your best shoes to walk across a building site would you ?

It's also a distinctly UK thing.

 

[Craiglxviii]

It's also a distinctly UK thing.

Anglo thing. It exists in the US too. Now there’s a thing, cultural and fashion trends tend to start in the US, migrate across to the U.K. in around 3-5 years and then to Europe 3-4 years after that. Motoring trends start in Europe and follow the reverse route...

 

[alexanderfoti]

Anecdotally

C63 4 X runflat tyres (255/30/19) - 2 different cracked rims.

4 x new non run flat tyres, no issues.

S65 4x Runflat tyres Pzero RF (275/40/19) - 1 cracked rim

4 x new non runflat tyres, no issues

Me thinks second hand car dealers buy them part worn as they are cheaper....

 

[Craiglxviii]

Well we can look at warranty recalls data. Let’s see what there is going...

 

[Craiglxviii]

No warranty recalls for wheel cracking on the E class, dating back to 1992.

 

[Craiglxviii]

Or the C, CLS, CL, SL or S klassen either for that matter. Plenty of recalls relating to fuel leakage or loss of power steering, a few to airbag deployment or seatbelt tension era but zero for wheel concern.

 

[JBell]

No warranty recalls for wheel cracking on the E class, dating back to 1992.

OEM's will never warranty a wheel for cracking, they just blame the roads

 

[umblecumbuz]

Difficult one.
To a degree, I am with the OP here.

If a buyer looks at a UK spec MB in an MB showroom, he (or she, of course) has a right to expect that it is fit for purpose in the UK.
He is not required to be tech savvy in all aspects of the vehicle, because to him it is a given that Mercedes have proven the package before offering it for sale. It is easy to say, 'He should have known better - or researched the model details more thoroughly' but consumer rights and common sense confirm that we cannot be expected to foreknow every pitfall when making a purchase.

His knowledge of the drawbacks of large wheel, ultra low profile tyres/runflats came after the purchase, and from bitter experience. Quite probably his driving style is not primarily to blame for the failures, because a growing number of posts across a variety of forums indicate that such a wheel/tyre combination can prove troublesome.

MB must be aware of this, and should accept some responsibilty - or alter the wheel/tyre combinations on their UK spec vehicles to suit.