Well I was always confused by MB, because for the 190E the stock tire is 185/65/15. Calculated options:

Stock:
185/65/15 ~ 24.5-24.6

Recommended replacement:
195/60/15 ~ 24.2

MB recommends as well:
205/55/15 ~ 23.9

So I guess the 190E can handle the whole range, but then you got the 16" tire sizes:

205/50/16 ~ 23.9-24.0

215/50/16 ~ 24.5

225/45/16 ~ 23.9-24.0

So the 215/50/16 is a good option for those who want a wide tire as possible on 16s with stock suspensions. The BFG Comp TA VR4 are decent here. I had them on my other 190E and I loved um because their wear was also very decent. The 225/45/16 can easily rub and are suggested for those who have some fender work, i.e. Evo II.

For 17" We have more options:

215/45/17 ~ 24.6

215/40/17 ~ 23.7-23.8

225/40/17 ~ 24.1 (only in the Nitto NT 555 by Discount Tire Direct, don't know if TireRack can get them for you, might want to check)

235/40/17 ~ 24.4

Now the 235/40/17 only work for some 16v and those who have the Evo II. They have the extra fender area for the 17x8s and the wider tires work well here. The 215/45/17 are the stock sizes recommended, however if you have any suspension mods, the tire could rub since the height is the same and width has increased. So the next size recommended size is the 225/40/17, which there is only 1 tire choice (It isn't a bad tire either,) so most go to the 215/40/17.

And for those who can find 18x7.5 in a proper offset, you will find them wearing:

215/35/18 ~ 23.9

285/30/18 ~ 24.7-24.8
Only 2 choices, the new BFG Scoorchers with the colored tread or the Nitto 450s which are much cheaper. The 285/30/options are for the Evo II with 18x10 (extremely low offset, single digits w/o spacers.) That is the ultimate wheel setup combined with H&Rs and no pads, the best you can get.

Hope this helps

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99 Mercedes-Benx ML 430 V8 w/custom TV, Video, UHF, speaker system
93 190E 2.6
2001 C240 V6 - maybe