polo1

Are there certain Mercedes 20" wheels that are more prone to cracking - or is it all of them?

1Action

I have a '08 ML63 and two of its AMG wheels cracked and needed to be repaired.

W205C43PFL

Theoretically forged wheels shouldn't have cracking issues or at least not as prone but that isn't the case in practice, it is hard for 20 inch to survive other than on German autobahn, it does look good though but then you are also sacrificing ride quality in a way.

Mason.Safari

I have my 2017 S500 since 24 Sept 2023... so far so good with 20" Wheels, maybe its too soon to say...also have runflat tires and when they need replacing with go with non runflat ones ...

W205C43PFL

Forgot to ask OP what tire pressure they had it set to now that I saw your tires. I assume your tire pressure is pretty high which might had helped with preventing cracking or it could be that OP's city is full of potholes.

Wolfman

Have had lots of MB 20" wheels on cars and never had one crack, even with potholes. On our S-Class, we had Pirelli P-Zero run flats and I blew one out in the first two weeks. Those were just crap tires. Replaced them with DWS 06 Plus and they were great. Tire pressure was in the low thirties if I recall...

In general all MB wheels are standard cast aluminum unless it's an AMG with optional forged wheels. These will be lighter and stronger... MB cast wheels are of normal/average quality...

nybenzo

I have these wheels the front driver side cracks regularly

1Action

these wheels develop cracks on the inner bead, which cause a very slow leak.

carlosinseattle

Cast wheels are more prone to cracking than forged wheels - forged wheels react with a bend which can be straightened, They "can" crack but normally deflect by bending. The 20" MB AMG wheels are forged while the regular 20" wheels are cast even some that have the AMG logo are cast. Low profile tires, expecially on a heavy car, are the real cause of the problem. It's not a defect in the wheels per se, more of a result of a lot of weight without much cushioning. A 20" wheel/tire combination might look nicer than 19's or 18's but you'll get a harsher ride and be more succeptible to cracks or bends. Run flat tires have thicker sidewalls, which make them ride stiffer, but that also means you transfer more road immperfections into the cabin. I don't think they add protection from wheels cracking, at least they didn't in my case. I had a 17 S550 4-matic sedan with 20" AMG style wheels, cast not forged - just like Mason, and constantly had bends and cracks on all 4. I live in Seattle and our roads aren't great, but not the worst. Just my $.02 cents.

will_atl

These crack, 3 of 4 have cracked on my S450, I just had to replace one of them (which has previously been repaired, twice), as it had 3 new cracks that couldn't be repaired. $900 for a new wheel!

MBenz07

Just got a '16 S550 with these wheels and wanted to know if you have RF tires and what pressure you are running? I am considering another 20" wheel or having these painted. Dealer fixed curb rash on all 4 but the finish is not as bright as I would like.

will_atl

I am on RF tires, and I run them mid to high pressure (based on the inside of the gas cap door), I have also found that I have to get them all rebalanced every 5-6 months (10,000 miles).

JohnLane

I had a wheel on the 221 S65 that had cracked on the inside and been repaired (poorly). Bigger issue with those wheels was chrome finish being dissimilar with aluminum it acted as a low voltage battery with tires pressing firmly against the bead for corrosion that made for air leaks that got fixed by replacing those wheels with forged aluminum. Cool run-on sentence huh!
Never a one crack or blowout in the 222 S65. My tires always have 44psi in them. Firm ride that handles well and is ready for that high speed run.

arniewhite

Dont try and weld them it does not work!!

W205C43PFL

Don't weld them and drop down to 19s.