MCF

I have 17x8 wheels on my luxury. I know that the AMG wheels that come optional on the sport models are the following sizes:

B66031468 ET48 18x8.5 with 245/40 tires in the fronts.

B66031469 ET54 18x9 with 265/35 in the rears.

With the two different wheel widths (8.5" and 9") and the different offsets (48 vs. 54) and tire sizes, will the 9" wheels in the back stick out of the wheel well more, less, or the same as the 8.5" wheels in the front? I am considering doing all four corners with the 8.5" wheels as that is what the 4matics come with (mine is not a 4 matic, just concerned about rear wheel sticking out too much). Anyone help out?

MCF

17x8 ET48 with 245/45/17 vs. 18x8.5 ET48 with 245/40/18.
From center of wheel to top of tire will be 12.84" for 17" wheel and 12.858" for 18" wheel so that is insignificant and gap between top of tire and wheel well will not be affected.

Now question about tire width and offset. Offset is same between two (48) and obviously 8.5" tire is 0.5" wider than 8" tire. Question is will the 0.5" wider tire 'grow' 0.25" inwards and 0.25" outward to fender or will tire 'grow' 0.5" only outward toward fender?

amdeutsch

Where are you getting that one tire is wider than the other one. Both are 245s. Tirerack has some good articles on their site. You might want to go there and read.

MCF

Hmmm...good point. I guess I assumed that since one wheel is 8" wide and the other is 8.5" wide that the overall width at outer diameter of tire would be 0.5" wider, but I guess this is wrong, right? The 8" wide vs 8.5" wide wheel is ONLY at the wheel/tire interface itself, not at the outer diameter of the tire, correct? Based on this, I should have no worry about the tire sticking out too far once mounted, right?

MCF

Ok..been doing some reading. Using an offset calculator, wheel will grow 6mm towards car and 6mm towards fender. Using same 245mm tire, for every increase/decrease of 0.5" in wheel width, actual tire section width will increase/decrease by 0.2". Based on this, if I go from 17x8" to 18x8.5" with 245 tires, the overall height of wheel/tire will be same not impacting gap between top of tire and wheel well and the actual tire section width will increase 0.2" (0.1" in either direction) which I would say is negligible. Any thoughts?

Sammyg96

Question, I have a 2008 E550, stock AMG 18 inch wheels, front Conti Pros, 245 x 40 x 18.......... anyone see an issue with replacing those with Michelin Pilot V rated 245 x 45 x 18......... one inch difference in size.......... thanks.....

lzamora

Bringing back this thread to life. Hopefully you guys masters of masters could help me out.

Let me explain my case. I own an E300 Avantgarde W212 2013 with the AMG package. The Datacard shows Avantgarde/Standard Suspension code 677. The wheels installed are the AMG Double-Spoke 18" with mixed tires (AMG Styling IV). Supposedly the front ones are 8.5 x 18 ET 48 and the rear ones are 9 x 18 ET 54.

As far as I googled, it says that "The tire dimensions reach from 245/40 R 18 for the front axle to 265/35 R 18 for the rear axle in case of mixed sets of tires"

I would LOVE to upgrade the wheels to the AMG triple-spoke alloy wheels. I have found them in two versions:

Front wheels AMG Styling VII - 8.5 x 19 inch ET43
Rear wheels AMG Styling VII - 9.5 x 19 inch ET43

https://www.kunzmann.de/shop/en/tire...gn-19-inch.htm

or (used on the R231)

Front wheels AMG Styling VII - 8.5 x 19 inch ET30
Rear wheels AMG Styling VII - 9.5 x 19 inch ET31

http://www.alloywheelsdirect.net/mer..._vii_wheel_486

I belive that the more similar the ET (offset) number is the better they will fit, but what really concerns me is the extra half inch in the rear which will translate in a wider tire. I believe that it will use 285/30....

So..... will any of the sets will work fine on my car, or I will have fitting problems??? On the first set (ET43) they claim that they should fit the W212 with no problem.

Thanks a lot for the help you gurus could give me!!!!