I have 16" wheels with Goodyear runflats. I haven't had any problems, but bought a set of 15" wheels with Continental non-runflat radials to run during the wintertime and maybe for autocrossing later. I have some questions, and need advice.

1. Will I need to have my odometer and speedometer reset since these tires are smaller than what I am normally running? Will the dealer have to do this?

2. Will the runflat sensor be affected in any way since the 15" non-runflats will be running? Will it have to be disabled with the non-runflats and then enabled again when I reinstall my 16" wheels/runflats this summer?

3. Will my fuel economy be affected by running a smaller tire? Will the computer need to be adjusted to reflect the effect of the tires?

Thanks a lot for any and all input.

There's nothing to reset - your speedometer will just be erroneous. Smaller diameter tire will mean you're going slower than the speedo says. Yea you might have to reset your tire monitor, no big deal. Fuel economy should be about the same.

The answer to #2 is yes. you will have to reset(not disable) your tire monitor when you change tires. I go from 16 to 17s.16s are regular tires the 17 are run flats. I think the answers to #1 and #3 are no and no. Not enough to matter.