alenko

I intend fitting 17" winter tyres to replace the 19" summer tyres I have on now. How will this effect the speedometer and odometer readings? I believe the TPMS can be easily reset,is that correct?

zarraz

just get the same rolling diameter and it will do nothing to the odo or spdo

ehsland

As long as the breaks fits it is the outer diameter of the tyre that is important.
But has anyone found any good looking 17" for AMG/Sport package? Please let me know in that case since I also need winter tyres.

alenko

At the risk of revealing myself as,thick. What does,maintaining the rolling diameter,mean?

ehsland

The total diameter of the tyre should be the same (or very close at least).

It is calculated as:
The size of the rims + the profile of the tyre * the with of the tyre * 2 (the rubber is on both sides of the rim). This is due to that the profile of an tyre is calculated as the percentage of the width (40 = 40% of the width)

An example:
The front wheels on my W205 is 18" 225*45 => 18*25,4 + 225*0,45*2 = 660mm
The rear wheels are 18" 245*40 => 18*25,4 + 245*0,4*2 = 653mm

Hence if you go with 17" you will have to increase the profile of the tyre. For example 17" 225*50 (gives 657mm in diameter).

alenko

Thanks for that reply.Every day is a school day.Much obliged.

RTX

Question: Are you going with the 17" because no available winter rubber on the 19"?
I'm on 18" and both types of tyres fit on the same wheels.

alenko

Yes,that is correct. I am informed that I only have the option of fitting 16" or 17",also I have been told that smaller diameter wheels are better suited to winter conditions anyway. But,hey,what do I know?

RTX

Check the possibility of fitting winter rubber on the 18".
Unless of course your dealer lends you the 17" for free (just calculates the cost of the rubber+fitment+storage).

alenko

I have 19" rims fitted now,so although it will be more expensive buying 17" alloys and winter tyres to fit them,I think the investment will pay dividends in the long run. Last winter there were several days it was impossible to use my car because of the icy hill where I live. I have been quoted,£1100,for rims and tyres.

c4004matic

Yes the more sidewall you have the better snow traction, however, the more you will notice the difference is handling when switching. 17 in is a good choice. MIchelin X ice is a very good tire but its by no stretch a great handler as is true with any studless snow tire. Remember all snow tires should be the same width (front and back): 225. If you have staggered wheels 245 rear 225 front, you need another set of rims too.

parkwood

In europe mercedes sell a winter wheel package including tpms but not the centre wheel bearing cover. For 17inch rims they cost 2000 euro for the set. Link below

http://www.mercedes-benz.fr/content/france/mpc/mpc_france_website/fr/home_mpc/passengercars/home/servicesandaccessories/accessories/winter_complete_wheels_2014.html

alenko

Thanks to all for the advice and information.

c4004matic

This is a good but, wow, expensive option. I got wheels and tires from tire rack for half that. The "cheap" winter rims are alloys that look almost as good as the OEM AMG ones!