R230 tyre sizes

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R230 SL55's with 19" AMG staggered rims should have 255x35xR19 96Y tyres on the front and 285x30xR19 98Y tyres on the rear.

The most important measurement is the offset (ET)
19" SL55 wheels are Front 8.5j ET30 and the rears are 9.5j ET31

You need to check the S Class wheels you are fitting to see what offset they are. I can't guess as there are different S classes depending on the year.
Look inside the back of the wheels and the ET should be embossed on a spoke along with the Part Number.
The reason those wheels don't fit is they are the wrong ET.

To get over it, you can fit a hubcentric spacer to bring the wheel away from the hub.
To determine what size spacer, use the correct ET for the SL above, front and rear, and take the figure away from the S class ET's front and rear.
(Eg ET 45 minus ET 30 = 15, so you need a 15mm hubcentric spacer and the correct wheelbolt 15mm longer than the ones you have)
Again, make sure you get M14 radius head bolts or the wheels can't be torqued correctly.

You can cross check which S class it came from on this site
Mercedes S Class Alloys (W220) - Alloy Wheels Direct

Its a minefield buying wheels from different models and expecting them to fit straight on:doh:
 
My 19's came off a CLS and are ET25 on front and ET28 on rear. They fit perfectly so small ET differences should be ok.
 
Thank you guys, for your replys and advise, i know my stuff, my current et front is 35 and the rear is 40, the new wheels i have (from s class)is 38 for both front and rears, should be fine, i think its the tyres sidewalls are too chunky
 
R230 SL55's with 19" AMG staggered rims should have 255x35xR19 96Y tyres on the front and 285x30xR19 98Y tyres on the rear.

The most important measurement is the offset (ET)
19" SL55 wheels are Front 8.5j ET30 and the rears are 9.5j ET31

You need to check the S Class wheels you are fitting to see what offset they are. I can't guess as there are different S classes depending on the year.
Look inside the back of the wheels and the ET should be embossed on a spoke along with the Part Number.
The reason those wheels don't fit is they are the wrong ET.

To get over it, you can fit a hubcentric spacer to bring the wheel away from the hub.
To determine what size spacer, use the correct ET for the SL above, front and rear, and take the figure away from the S class ET's front and rear.
(Eg ET 45 minus ET 30 = 15, so you need a 15mm hubcentric spacer and the correct wheelbolt 15mm longer than the ones you have)
Again, make sure you get M14 radius head bolts or the wheels can't be torqued correctly.

You can cross check which S class it came from on this site
Mercedes S Class Alloys (W220) - Alloy Wheels Direct

Its a minefield buying wheels from different models and expecting them to fit straight on:doh:


okay, so before i head out to get new tyres, can anyone confirm that the tyres i need for 19" wheels are 255x35xR19 and 285x30xR19 respectively.
or to be safe and give more clearance should i go 255/30/19 on the fronts?
 
okay, so before i head out to get new tyres, can anyone confirm that the tyres i need for 19" wheels are 255x35xR19 and 285x30xR19 respectively.
or to be safe and give more clearance should i go 255/30/19 on the fronts?

If you go for 255x30 on the front, you'll have to reduce the rears to 285x25 to keep the rolling radius correct and it will be like riding on elastic bands.
Here is the link for R230 alloys. Click on any 192 wheel, scroll down and the tyre size is confirmed as 255x35 front and 285x30 rears
Mercedes SL Class Roadster Alloys (R230) - Alloy Wheels Direct
 
I would stick to 255 35 19 front and 285 30 19 rear. If you go 30 and 25 you will further ruin the ride. I am assuming they are the recommended 19" AMG wheels for your car. If they are aftermarket then it depends on the rim width/offset and is a whole new ball game.
 
I would stick to 255 35 19 front and 285 30 19 rear. If you go 30 and 25 you will further ruin the ride. I am assuming they are the recommended 19" AMG wheels for your car. If they are aftermarket then it depends on the rim width/offset and is a whole new ball game.

i will stick with the recommendations. they are amg wheels from an s class with an offset of et38, my oem wheels are et35 and et40 so should be okay with 255/35/19 and 285/30/19s with those offsets.
 
I have a 2011 R230 Facelift SL350 currently fitted with 19" staggered rims.

I live on a BOAT (Byway Open to All Traffic) which is pretty rough, like many of the rural roads around here, and accordingly I have decided to switch to 17" or 18" rims to improve the ride.
I have the 952 Sports Package, and it has been suggested that I am not able to fit wheels smaller than 18"; is this correct please?

Assuming that I go for smaller rims do I have to have staggered rims, or can I get by with the same size font & rear? I'd also appreciate any recommendations on this proposed switch. I'm retired and my SL will mostly be used for long distance summer touring, generally A roads or Motorways in UK, France, Spain and Italy

NJSS
 
Another question I fear?

What are the pros & cons of staggered rime?

I am considering Michelin Pilot Sport 255/45/R17 all round on MB 7x8.5 5 twin spoke wheels (A23040139)- any thoughts please?

NJSS
 
I have a 2011 R230 Facelift SL350 currently fitted with 19" staggered rims.

I live on a BOAT (Byway Open to All Traffic) which is pretty rough, like many of the rural roads around here, and accordingly I have decided to switch to 17" or 18" rims to improve the ride.
I have the 952 Sports Package, and it has been suggested that I am not able to fit wheels smaller than 18"; is this correct please?

Assuming that I go for smaller rims do I have to have staggered rims, or can I get by with the same size font & rear? I'd also appreciate any recommendations on this proposed switch. I'm retired and my SL will mostly be used for long distance summer touring, generally A roads or Motorways in UK, France, Spain and Italy

NJSS

Do you have the bigger brake calipers on the Sport package? If so, I doubt 17" alloys will fit so to be on the safe side a step down to 18" may be wiser? Is it possible to test fit a wheel and tyre before commiting to buy?
The recommended set up with 18" rims is a staggered set up with 8.5j fronts and 255x40x18 tyres and on the rear 9.5j with 285x35x18 tyres The ET or offset is 35 front, 40 rear.

The set up you suggest for 17" alloys is perfect, but not knowing if the wheels will fit over a sport package caliper it's difficult to recommend them.
 
AMGeed

Many thanks. I'm going to try 17" if I can.

Is there any disadvantage, or benefit in not having staggered rim sizes? The suggestion of 255/45/R17 all round on MB 7x8.5 5 comes from a local tyre store.

NJSS
 
AMGeed

Many thanks. I'm going to try 17" if I can.

Is there any disadvantage, or benefit in not having staggered rim sizes? The suggestion of 255/45/R17 all round on MB 7x8.5 5 comes from a local tyre store.

NJSS
I think its aesthetics, bigger wider tyres just look better on some cars.
 
AMGeed

Many thanks. I'm going to try 17" if I can.

Is there any disadvantage, or benefit in not having staggered rim sizes? The suggestion of 255/45/R17 all round on MB 7x8.5 5 comes from a local tyre store.

NJSS


The benefits of not having staggered setup is that it gives you much more flexibility when replacing tyres, and also that you can rotate the wheels back-to-front at each service which maximise the service life of the tyres. And probably slightly better mpg, though probably not to any noticeable level. Additionally, if (like me) you carry a full-size spare in the boot, there's the minor benefit that in the event of a puncture you can continue your journey as per normal. But obviously you lose the cool look of the wider tyres at the rear.
 
The benefits of not having staggered setup is that it gives you much more flexibility when replacing tyres, and also that you can rotate the wheels back-to-front at each service which maximise the service life of the tyres. And probably slightly better mpg, though probably not to any noticeable level. Additionally, if (like me) you carry a full-size spare in the boot, there's the minor benefit that in the event of a puncture you can continue your journey as per normal. But obviously you lose the cool look of the wider tyres at the rear.
If the profile of the tyres is correct then the spare will fit front or rear in a staggered setup.
 
If the profile of the tyres is correct then the spare will fit front or rear in a staggered setup.

Correct, however at that point the car will have one wide tyre and one narrow tyre on the same axle at the rear, which is not ideal in terms of ESP, ABS, and suspension wear (uneven stress). Not an issue for a short journey, and definitely much much better than a spacesaver, but being OCD about these things (and many other things...) I carry a full-size spare in the boot, which is an original MB alloy wheel identical to the other four, with a good tyre the same size as the other four, so that I can continue my cross-Continent European trip unhindered at full Autobahn speeds (not that I have ever done such a trip, nor am I likely to do one in the foreseeable future, but this has nothing to do with it, mind your own business!). And what if I have another puncture before I had the opportunity to repair the first one, you ask? For such an eventuality I also carry an original MB TIREFIT inflater that comes with the canister of gooey stuff 😎 . Needless to say that I carry a long bar for releasing the wheel nuts, wheel chock, a collection of yellow and red hi-viz vests, emergency flashing beacon... OK I'll stop here 😊
 
Many thanks everyone for the advice given above, much appreciated.

I'm about to take the plunge and go for 17" Mercedes 5 Twin Spoke Wheels the part number of which is, I think B66474472 - A2304013902; the width is 8.5 & the offset is ET35, PCD 5 x 112.

As my car has the 952 sports package I'm going to try a test fit, both front & rear. Do I have to have tyres on the rims for a test fit, or do I merely need to ensure the wheels clear the calipers?
 
I did see on another post that you can fit upto 305 on the rear

I might look at the 17" for winter tyres myself, i never realised that they fitted
 
An update.

I successfully fitted 255/45/ R17s all round, and have done a few miles with them. Improved ride, but still bumps & thumps more than I like on our under maintained roads.

Someone suggested one can fit 16" wheels, which would no doubt improve things further, but I haven't seen or heard of it being done.

NJSS
 

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