FWIW, I suspect that the LEAF's OEM tires may have thinner sidewalls
than the same make, model and size tires mounted as replacements.
Two or three years ago, there was a rash of sidewall failures on Gen II Prii
reported on PRIUSchat. So what's up with that?
Subsequently, I ran up on the sharp corner of a granite curb used --
allegedly to minimize damage from snow plows -- in Portland, ME, with
four people in my Gen II. The left rear tire sidewall failed; it looked like
it had been cut with a knife from tread to bead.
My Touring model runs 16 in. Bridgestone Potenzas vice the standard 15 in.
Goodyear Integrities. It took 24 hrs to have a matching tire shipped in
from a Boston warehouse. The tire was mounted and I drove off.
At 60K miles it was time for new tires all around. I was happy with the
Potenzas; good tire wear and lifetime MPG of 50.4. So I got four more
Potenzas. During the demounting/mounting I was able to directly compare
the OEM tires with the replacements. The sidewalls of the OEMs showed
signs of being thinner than the replacements. They felt thinner, and
they were much easer to bend/flex by hand -- sorry, I didn't have a
micrometer in my pocket that day.
Why would Toyota mount thinner sidewall tires as OEM? IIRC, on
PRIUSchat it was thought that the assumedly lighter tire might add a
tenth or two to the MPGs for FE bragging rights...
and they might be a handful of dollars/yen cheaper as well.
I dunno. But it wouldn't surprise me to learn that Nissan was up to the
same tricks for MPGe/range bragging rights and lower costs.
A member getting a new set or single tire matching the OEMs could
do a much better comparison than I did to confirm or deny.