Hi Eric,

Using https://tiresize.com/calculator/, your 225/55-17s seem to be 754
revolutions per mile, and the 215/60-16 seem to be 771, so it looks like
the best bet is either 215/55-17s (767) or 225/50-17s (780).  You could
even look at 235/50-17s (769) if you could run something that wide on
your wheels.

They have links to look up exact tyres - I'd be looking at (LT) truck
tyres and I like my Geolandars (15", so no use to you).

Different manufacturers will have slightly different revolutions per
mile (due to tread height) but this should get you close - you can even
figure out the exact rpm if you look up your current 16"ers.

toodle pip,

On 8/18/2025 05:59, Eric Caron wrote:
> Hi listers,
>
>          I have a set of 9 year old tires.  And one just developed a broken belt and a bulge.
>
> So, looking to replace all 4.
>
> This is on 17 inch wheels direct bolt on.
>
> I want to reduce the diameter a bit to get closer to stock and also, and a few other reasons.
>
> The current diameter is
> 225 55/17
>
> The other van is running the diameter I want on a
> 215 60/16
>
> How do I get the same diameter on the 17 inch wheel?
>
> Either 215 or 225 should be fine. Though having both vans the same at 215 might be nice.
> I have tried to use AI to figure out exact diameters, but get different answers.  Also som variation on the on line tables when I looked in the past.
>
> So, tips on available tires in a 17 wheel but with the diameter of the 215 60/16 would be incredibly helpful.
>
> Eric Caron