S-Class (W223) Blowouts on Front Tires (W223 S450, 21”) — Advice Needed

[xvxpft]

Hello everyone!
I could really use some advice:

Vehicle:
– MB W223 S450 4Matic 2024 (VIN: W1K2231611A233119)

Wheels:
– Summer tires: Pirelli P Zero
– Winter tires: Pirelli Sottozero 3 in the rear, Michelin Pilot Alpin 5 in the front — a mixed setup due to issues with one full set (the original front tires performed terribly, so they were replaced)
– Front tire size: 255/35 R21 98Y
– Rear tire size: 285/30 R21 100Y
– Wheel specs: 9J x 21H2-N ET34 (front), 10J x 21H2-N ET48 (rear)

ISSUE:
I’m constantly experiencing sidewall damage (blowouts) on the front tires.

All tire and wheel specs match factory recommendations. I’ve tried adjusting the tire pressure according to both full and partial load settings (though it’s usually just 1–2 passengers in the car). The wheels are OEM.

Has anyone encountered a similar issue?

The most obvious solution seems to be downsizing to 20” wheels — but I’d really prefer to avoid that.

I’m considering a setup with a slightly higher profile — 255/40 in the front and 285/35 in the rear (similar to what AMG and Maybach models use).

However, I’m concerned these might not fit properly: they could rub, cause clearance issues, or simply not mount at all. There’s also a risk this setup could negatively affect the car's performance or safety, especially since the label on the fuel cap specifically advises against using non-standard sizes.

Has anyone run 21” wheels with 255/40 fronts and 285/35 rears on a regular S-Class (non-AMG, non-Maybach)?

What would you recommend?

 

[Centurion]

Hello everyone!
I could really use some advice:

Vehicle:
– MB W223 S450 4Matic 2024 (VIN: W1K2231611A233119)

Wheels:
– Summer tires: Pirelli P Zero
– Winter tires: Pirelli Sottozero 3 in the rear, Michelin Pilot Alpin 5 in the front — a mixed setup due to issues with one full set (the original front tires performed terribly, so they were replaced)
– Front tire size: 255/35 R21 98Y
– Rear tire size: 285/30 R21 100Y
– Wheel specs: 9J x 21H2-N ET34 (front), 10J x 21H2-N ET48 (rear)

ISSUE:
I’m constantly experiencing sidewall damage (blowouts) on the front tires.

All tire and wheel specs match factory recommendations. I’ve tried adjusting the tire pressure according to both full and partial load settings (though it’s usually just 1–2 passengers in the car). The wheels are OEM.

Has anyone encountered a similar issue?

The most obvious solution seems to be downsizing to 20” wheels — but I’d really prefer to avoid that.

I’m considering a setup with a slightly higher profile — 255/40 in the front and 285/35 in the rear (similar to what AMG and Maybach models use).

However, I’m concerned these might not fit properly: they could rub, cause clearance issues, or simply not mount at all. There’s also a risk this setup could negatively affect the car's performance or safety, especially since the label on the fuel cap specifically advises against using non-standard sizes.

Has anyone run 21” wheels with 255/40 fronts and 285/35 rears on a regular S-Class (non-AMG, non-Maybach)?

What would you recommend?

What are your local roads like? Do you mount curbs or drive through pot holes?

 

[sako97]

Hello everyone!
I could really use some advice:

Vehicle:
– MB W223 S450 4Matic 2024 (VIN: W1K2231611A233119)

Wheels:
– Summer tires: Pirelli P Zero
– Winter tires: Pirelli Sottozero 3 in the rear, Michelin Pilot Alpin 5 in the front — a mixed setup due to issues with one full set (the original front tires performed terribly, so they were replaced)
– Front tire size: 255/35 R21 98Y
– Rear tire size: 285/30 R21 100Y
– Wheel specs: 9J x 21H2-N ET34 (front), 10J x 21H2-N ET48 (rear)

ISSUE:
I’m constantly experiencing sidewall damage (blowouts) on the front tires.

All tire and wheel specs match factory recommendations. I’ve tried adjusting the tire pressure according to both full and partial load settings (though it’s usually just 1–2 passengers in the car). The wheels are OEM.

Has anyone encountered a similar issue?

The most obvious solution seems to be downsizing to 20” wheels — but I’d really prefer to avoid that.

I’m considering a setup with a slightly higher profile — 255/40 in the front and 285/35 in the rear (similar to what AMG and Maybach models use).

However, I’m concerned these might not fit properly: they could rub, cause clearance issues, or simply not mount at all. There’s also a risk this setup could negatively affect the car's performance or safety, especially since the label on the fuel cap specifically advises against using non-standard sizes.

Has anyone run 21” wheels with 255/40 fronts and 285/35 rears on a regular S-Class (non-AMG, non-Maybach)?

What would you recommend?

Hi there @xvxpft - I have a S580 with the same 21’ AMG wheels. Since I got the car in 2023, I’ve had 6 blowouts on the Pirelli P Zero MO-S, front and rear (metro NYC area). A bent rim on two occasions. It was a nightmare. Every pothole and manhole, I was either swerving or bracing for impact and another potential blowout. It’s terrible how soft the Pirelli sidewalls are, and the rims being aluminum makes things worse. For a while it was the only tire option on the market for S-Class spec. I love the design of the wheels, so I also didn’t want to revert to 20”.

Since the S63 is out, I switched to 255/45 and 285/40 Michelin’s from the S63e. The difference is night-and-day. The ride is even more supple, and I haven’t had a blowout since January, when I made the switch. No rubbing or clearance since it’s a Mercedes OEM spec tire for a variant of the same car. They’re costly, but worth the peace of mind.

FYI - Maybach tires wouldn’t work as the rear rim supports 265/35/21 tires.

 

[jasonmiller]

Sidewall blowouts on 21" low-profile tires are common on the W223. Mixed winter tires may worsen the issue. Upsizing to 255/40 front and 285/35 rear could help but may cause rubbing or clearance issues on non-AMG models. Safer option: switch to 20” wheels or use reinforced matching tires on 21s.

 

[martinbo]

Sidewall blowouts on 21" low-profile tires are common on the W223. Mixed winter tires may worsen the issue. Upsizing to 255/40 front and 285/35 rear could help but may cause rubbing or clearance issues on non-AMG models. Safer option: switch to 20” wheels or use reinforced matching tires on 21s.

Thank you, generative AI!

 

[klier]

Thank you, generative AI!

Great bot! Likes the Ferrari V8.

 

[sako97]

Thread revival here - there’s a few large class action lawsuits that has forced MB to drop the 21” wheel entirely in the US for 2026-on, with a couple other regions following suit. How an engineering committee approved a S-Class with aluminum 21” inch wheels, with very low profile tires from Pirelli as MO-S designated (with it’s spotty reputation on F segment cars) is beyond me.

As much as I like the design - after fitting 20” winter season wheels, I will likely stick to this set up for piece of mind.

I understand why BMW mostly downsized the wheel offerings on the G70 wheels due to the significant weight increase this generation, though the wheels they offer look small due to the car’s mass.

Shame - good design but an engineering mistake.