I'm running 265/75 16 tires on my 94 4.0 ZJ. I did the math and to get the overall (distance travelled per revolution of the engine) gear ratio close to factory with 3.73's and 215/75r15 tires would be to swap out my r&p gears in my Danas (30&35) for 4.10's or if I go to 285 (33") tires, 4.56's.
I have to decide, so, the 265/75 16 CooperSTTs fit perfectly with the 4" Zone suspension and the RLC front bumper. I want to step up to 285 tires. Without flares, give me some advice on what I need to do to run (only an inch or so taller tire) if anything at all. Then I'll know what gears to buy. Thanks

 

The first thing would be don't waste money on the Dana 35, you can find a Ford 8.8 out of an explorer with 4.10s already, and swap it in, then regear the 30 to 4.10.