245/70-16, yes, but I don't think the 265/70-16(isn't that pretty much the same size as a 245/75-16? If so you're gonna need some lift), 275/70-16 I doubt. I think that's closer to a 32" tire, and that'll need about 4" of lift, maybe a little more.
Honestly, I think it's the higher center of gravity. It's a Jeep, not a sports car, so your driving style needs to be adjusted as such. It's a lot harder to roll an A3 compared to our Jeeps.
2011 KK - Skyslider - JBA Adjust-A-Strut - OME 731 - Bilstein Shocks - JBA UCA- 245/75-16 Duratracs