I assume that you plan to use a tire that would maintain the overall diameter of the 15" tire currently in use. If so, moving from a 15" to 16" would require you to use a tire with a shorter sidewall, which generally allows less sidewall flex, resulting in a tire more responsive to steering inputs. The downside is that the shorter sidewall will result in a rougher ride.

That's correct. I like the more responsive steering aspect.

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

16x7x20mm VS 15x7x20mm, what would be the best tire size for the 16" wheel? And what are the opinions about the rims: top is 15" and bottom pic is 16" rim?

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

I love the 16's on my SD.

Ride quality is still Mercedes, and cornering and road feel are better.
The combo I am running is almost exactly the weight of the 14" bundt set, so there are no effects from variations in the unsprung weight.

Have not noticed any change in fuel economy either.

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On some nights I still believe that a car with the fuel gauge on empty can run about fifty more miles if you have the right music very loud on the radio. - HST

1983 300SD - 305000
1984 Toyota Landcruiser - 190000
1994 GMC Jimmy - 203000

https://media.giphy.com/media/X3nnss8PAj5aU/giphy.gif

I like the look of the top rims, however I think 16" s would give you better handling.

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'07 Yukon 2500
'13 Subaru Outback 3.6R
'13 Orbea Carpe 9-speed

Currently Benzless
Formerly: 300TD, S600, E55, 560SEL

---= The forest breathes, listen.
-Native American elder