I’m surprised you’ve received no feedback whatsoever. Most of these guys are firm believers in lifts. They’re highly critical of larger tires without them.Looking at getting some aftermarket wheels with the following specs:
SIZE OFFSET LIP DEPTH
17X9 -12 4.05"
The tires will be 285 75 17.
My question is will these work without height and width changes to the vehicle setup?
I think you misread.......It's a 17x9 wheel which is what I run with a 285/70-17. The offset is -12mm per his description.That is a pretty wide wheel for that size tire. Check your tires specs, but you may find that size tire is made for a 7.5" - 9.5" wheel.
As far as fitting that tire size, I think you will either need a lift, flat fenders, or both (depending on how much lift you go with). You should not need wheel spacers with that much offset, but that wheel size is pretty bad for that tire size. The wheel would be wider than the tire.
I would read the "what's the largest size tire I can run on a stock Jeep?" thread.