I ran 235/ 75/ 15s/ AT tires on my Tracker with no lift and then added 2" body lift. The tires didnt have any problem on stock alloy wheels either way. They barely rubbed on the passenger side before I lifted the body on absolute hard over to the right steering, and now no rub. They actually measure 29 inches in diameter with about 7" of tread width. With the 2" lift I could go to 30" diameter by about 8" of tread width and probably would not rub, or only a little.
Had a real hard time with that drivers side besky brake line on my lift cuz the mount was corroded and it was hard to get it realesed. Had to spray it for days with PB blaster (thanks to tips on this forum) to get it loose. did the lift with not problem after that. Reattached the brake line to the mount after the lift and it is fine now.
I am wheelin off road quite well with the 235's in dry sand and wet sand and slippery but shallow mud. Even do well in deep jeep track ruts. I ride cross country in open fields with obstacles, brush, ruts, holes, swampy sections, sandy mud, No locker or other add ons and have a real hard time getting stuck. And again I am on 235 AT's which are minimally aggressive tread!
In fact I am amazed at what this little Tracker can do compared to the jeeps I've had in the past!
Thinking myself of going to 30" or 31" mud terrains or more agggressive All Terrains with spacer lifts just to get a little more clearance. 1 1/2 spacer and about an inch more of tire would total about 2 full inches of extra clearance. I am already clearing everything I want to clear so the added would just be insurance.
Keep in mind I am wheeling in Central Florida so your conditions will be different.
I think a good locker would be a great add on!