cracking alloy wheels

[angry1961]

hello, first post on here. I have an e-class coupe, factory fitted with 20" alloys and run flats. my problem is that my alloy wheels keep cracking and need to be replaced, 5 so far in 12 months! I do no more than motorway and A road driving so think this is unacceptable - has anyone else had the same issue and any ideas on how to move forwards as I have lost confidence in the suitability of the vehicle

 

[LostKiwi]

It's not the vehicle that's the problem, it's the carp roads. You'll also have issues if you straddle speed humps as the weight of the car is put into the unsupported inner edge of the wheel.
I don't know why people have this fascination with huge alloy wheels. 20" wheels and UK roads don't mix.

 

[angry1961]

It's not the vehicle that's the problem, it's the carp roads. You'll also have issues if you straddle speed humps as the weight of the car is put into the unsupported inner edge of the wheel.
I don't know why people have this fascination with huge alloy wheels. 20" wheels and UK roads don't mix.

thanks for the input, I guess the question is why I was not warned when buying the vehicle for a lot of money that it wasn't that suitable for UK roads?

 

[dry run]

thanks for the input, I guess the question is why I was not warned when buying the vehicle for a lot of money that it wasn't that suitable for UK roads?

I guess because you probably wouldn't have bought it!

 

[Frontstep]

thanks for the input, I guess the question is why I was not warned when buying the vehicle for a lot of money that it wasn't that suitable for UK roads?

That thinking would also rule out stiletto heels and size 32 lycra pants, people have to take a bit of responsibility for their purchases.

 

[sonic]

I run 18" summer wheels because they came with the car, & 17" winter wheels as they are the smallest that will fit.

 

[anyweb]

my E400 coupe has 20inch wheels and I haven't had such issues, but then again I live in Sweden and maybe our roads are in slightly better condition than yours ? are you hitting a lot of potholes ? surely you must notice it especially if you've cracked 5 wheels that's crazy. Have you checked that the pressure in your tires matches what is recommended on the fuel cap lid ?

 

[ajlsl600]

5!! Would seem that yr driving has not changed since the first. Every time I rtn to the UK the road condition shocks me.. Everything about the place is becoming third world like. Cept the snowflakes and P. C brigade.

 

[SmartAmg]

To me it sounds like the alloy wheels are crap, is it the run flats? don't know, might be? nothing to do with being 20s, I've had a few car's with 20s and no trouble at all, some think that 20s are the work of the devil, not so, imo, and they look fantastic!

 

[Blobcat]

If you straddle cushion speed bumps you’ll bend/crack alloys regularly.

The fashion for huge alloys just leads to expensive repairs to wheels, suspension and a regular replacement of knackered tyres along with a trip to a chiropractor or two...

 

[Blobcat]

thanks for the input, I guess the question is why I was not warned when buying the vehicle for a lot of money that it wasn't that suitable for UK roads?

The vehicle is suitable, it’s how it’s being used that is the cause of the failures. I understand that this isn’t what you want to hear but it’s what you’ll get from Mercedes.

 

[dry run]

I ran an w211 E320 on 19" cheap AMG replicas (less than £600 for 4) and never had a problem with the alloys - although a few GY Assy tyres gave out.

 

[mioba]

Must say it seems like driving style to me.

Whats the tyre profile, anything low below 40 will cause you headaches on UK roads.

I have 20 on my W251 and they are fine (45 profile) sure I avoid potholes and take it easy over humps

 

[brandwooddixon]

This isn't an issue that affects just Mercedes.

The simple fact is that you have to be more vigilant for potholes, bumps and speed control measures such as road humps.

As mentioned when approaching road humps, don't straddle them, instead run one wheel directly over the middle of it as this will even out the stresses placed on the wheel rim.

On some roads I find myself driving like a drunk man as I slalom around the potholes and the lowest profile that I have is 35 on my 20" rims, I only suspect that on an E-class the profile is even lower.

Whichever way that you look at it the amount of rubber between the rim and the road surface has a direct bearing on the amount of protection afforded to the wheel.

 

[tonysmbb]

This isn't a new issue by any means. Eight years ago I decided that I wanted the smallest diameter wheels available on my chosen model (E class coupé) simply due to the poor condition of our roads and not seeing the sense in the obsession in the UK with large wheels and subsequent very low profile tyres. IMHO it's marketing madness. I still had 45 profile tyres, which I think is still quite low profile; after all, it doesn't seem that long ago that 70-profile was the latest marketing 'must-have'.

A friend has a Range Rover with 22 inch wheels with, IIRC, 40-profile tyres, and then wonders why it isn't very good for it bouncing up and down kerbs. Now, with an older Rangie on decent profile tyres it wouldn't have been a problem but he thinks the wheels look 'the business'. They might do, it's just that they're not very practical.

Having said that, if five wheels have cracked in such a short period of time you'll either need to prove a structural weakness in the design or, with respect, change driving style or route. If you like the car you might find it cheaper to bite the bullet and simply buy a set of smaller, factory-spec, wheels which might not look as good but might be more practical. Our roads are a mess, certainly the worst I've come across (except for Belgian motorways) throughout Europe, but they have been for at least ten years now.

 

[davyhoogy]

Alot of it is due to run flats. They have are made with steel to help you drive when deflated. Therefore less give in the tyre. So more impacts on the rims = cracks

 

[tonysmbb]

OP

If you're monitoring this thread, there's one currently running on PH under Mercedes section, W213 cracking 20" alloys. It would seem that it's not just you.

Might be worth reading.

Eta, I also see a similar thread on another MB forum, a suggestion being that there is an issue with 20" wheels, possibly cast (as opposed to forged) ones. Numerous cracks after a long continental trip with no potholes was the issue on question.

 

[hfuhruhurr]

I've had two similar issues with my E350. A slow puncture which on investigation was found to be caused by a cracked wheel. It was undoubtably caused by a pothole. We have many poor roads in North Devon (UK) and new potholes appear regularly. The thin nature of the low profile tyres gives no protection at all. It's my only fault with the car.

 

[JBell]

It is not always the wheels, the Run flats put massive pressure through the wheels as their sidewalls are so stiff

 

[Mattross]

Hello, I appreciate this is an old thread but I’m new to this forum. I have an e220 coupe with 20 inch wheels and I’m experiencing the same issues. Comments about driving style are not helpful, simple fact is that you can’t always avoid potholes or undulations in the road and our roads in the uk are terrible. Having had the alloys repaired I’ve been told by garages that it’s common, not just with MB, BMW too, been to ATS for new tyres and told the same. I’ve had a c class before with 19’s and low profile run flats and never had an issue. I’m told the main issue is as others have said - 20inch rims, low profile and run flat tyres. MB have been useless, I contacted them suggesting they’d got a specification issue, they simply asked me to contact the dealer?! They cited there being no safety recalls so they couldn’t or would do anything. The dealer was also issueless, prior to knowing the wheels were cracked there was a vibration issue, the dealer told me it was down to the cracks, it wasn’t, it was a faulty tyre they fitted where the foam insert had come loose meaning the wheel was forever out of balance. My issue is I could accept replacing the wheels, albeit at £1000 each maybe once, but what’s to stop it happening again? It’s a bottomless pit potentially. It’s a shame as it ruins what is generally a really nice car. Has anyone had any positive feedback on this or has everyone simply rolled over and had to cough up?