setlur

I own a 2011 E350 4MATIC sedan. The local tire dealer has installed Michelin Alpin PA3 winter tires size 225/50/R17 on new 17" rims. The OEM all season tire size is 245/45/R18. Is the installed winter tire correct for this model. I cannot find this tire size recommended anywhere on the internet. Please help. Thanks.

RichardM98

Well, for starters welcome to the W210 forum -

FYI there is a W212 forum which covers your model.

As for your question, I would start by comparing the circumference of the front and rear tires.

A useful calculator is here - http://www.tiresizecalculator.info/

You generally want 3% or less difference to avoid issues with electronic braking and stability packages.

There is also a Tires forum and each year about this time there is a thread covering winter tire/wheel issues.

setlur

Thank you very much to RichardM98. I made a mistake in my OEM tire size. It should read 245/40//R18. I checked with tiresizecalculator.info. The following is the comparison. My next question is whether it is acceptable to mount these tires on the car for MB warranty coverage. I paid half the price for these tires compared to MB retail winter tire price based on OEM recommendation which is a Pirelli Sotozero.

I would very much appreciate your reply. Thanks.
<table><tbody><tr><td width="50px">
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<table><tbody><tr><td style="text-align: left;">Original tire
Sidewall: 3.86 in
Radius: 12.86 in
Diameter: 25.72 in
Circumf: 80.79 in
Revs/mile: 784.25
</td><td width="75px"> </td><td style="text-align: left;">New Tire
Sidewall: 4.43 in
Radius: 12.93 in
Diameter: 25.86 in
Circumf: 81.24 in
Revs/mile: 779.95
</td></tr></tbody></table><table><tbody><tr><td width="50px">
</td><td style="text-align: left;">
Speedometer reading with new tire is 0.55% too slow.
When your speedometer is reading 60mph you are actually traveling 60.33mph.</td></tr></tbody></table>
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RichardM98

I don't think there would be a problem but I'd suggest asking dealer to be sure.

MBFLO

Why did u install new rims and tires on the car . ?You have a 4 matic . I would guess it come with Pirelli all seasons unless you have a sport model . Not sure what the price difference was but you could of just got another set of winter tires and installed them on your 18 inch factory wheels then swapping the tires back in spring

ohlord

245/45/17 or 245/40/18 OEM are the 2 sizes listed as winter use tires on a w212 2011
for E350 4matic it would show the 17 in rim as not available from the factory.
The ones they fitted are close in diameter but about 4/5 of an inch to narrow for the proper specs.
Why the tire shop did not look in your owners manual is just a failure of intelligence.
It is there in big bold printing.
Don't you have a manual?
Always consult with it before hunting out on the internet.
It would have saved you the long trip here to discover the tire dealer sold you non oem sizes.
What rim width and Et did they sell you? that maybe wrong also.