I wondered the same thing. I just picked up my '23 GT2 Monday and I'm about at the end of my first tank, which I'm sure is 87 as the dealer filled it up. I definitely plan on running 93 the majority of the time, as I've had to run it in all my other vehicles over the past 7-8 years, so I'm use to that bill. Have you tried it yet? If so, what's your thoughts?