[Toyotiac]

I don’t think Chevy publishes that information but it’ll be fine. Lots of post about people using them with no one complaining of failures or other issues. Just make sure the tires are the correct load rating.

Everything I’ve read suggests the load rating is supposed to be stamped on the back of the wheel, but all the pics from eBay sellers have no numbers that could be construed as a load rating. EDIT: I talked to the parts dept at my local dealer and was told GM does not publish those numbers.

 

[Toyotiac]

But my initial question stands - the speedometer would be wrong, so you'd have to "tell" the computer the new wheel size to correct the speedometer, right? I was wondering if the computer would then lower the max speed of the vehicle because the wheels have to spin faster to maintain the same groundspeed... or if it will just limit you to 93mph whether your tires are 14" or 18"?

But I guess it's moot given what others have said - that the actual tire size ends up commensurate because the increased sidewall diameter makes up for the smaller wheel hub diameter.

The 15” wheel/tire combination I’m looking at has the same diameter as the stock 17”, so no recalculation is necessary.

 

[Toyotiac]

I'd go with tires that have a taller sidewall giving you the same overall diameter. I think the right size tire is 205/65R15 on a 15" wheel. See how the revolutions per mile compare to the stock 17" tire size.

Yes, this is the size I’m looking at. A Bolt owner who made this change made a YouTube video about his lower consumption. And a recent acquaintance (fellow Minnesotan 😉) who made the same change told me of his similar lower consumption.