A 265/75/16" tire is technically 31.6" x 10.5"; a 235/85/16" tire is technically 31.7" x 9.25". However, usually I've seen the 235/85 tires only as an "E" rated tire, where the 265/75 tire can be found as a "D" rated tire. Might make a difference in ride the D vs. E rated tire. Otherwise they're about the same size as a 31" x 10.5" on a 15" rim (and often as a "C" rated tire).
And if you're lifting your ZJ and putting taller tires on it, you'll want to re-gear the axles. We went from the factory 3.55 (or was it 3.7-something?) to 4.10 gears with the 31" tires. The Dana 35 axle is weak (which is what you probably have), and the Dana 44A has limited gearing and traction device options (and has an aluminum center section). Swap out the whole rear axle with a new one made to your specs (we had a TrueTrac put in ours).
Jeep ZJ Please read our Jeep FAQ Page for all questions related to Jeep complete assemblies.
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