Thought I jump in since I am running 33" tires. I have the 33x12.5-15 BFG Mud, and I'm very happy with them. I thought they would be as loud as Goodyear MT/R (had them on my Jeep), but they were surprising tolerable. Don't get me wrong, you will feel and hear them, but it's not too bad. The BFG A/T is another great tire that I had in the past. I had close to 60k before getting new tires.

As for lift, you'll need about 3". I installed the 3" body lift, and they cleared with minor rubbing in the front where I had to do some trimming. Main reason mine are tight is that I'm running 15x10 wheels with 4" BS. If you can stick to 15x8, they should fit like a glove w/o any problem.

As for power with stock gears, like Jake97T said, they should be fine. You'll feel the lack of power, but it's far better than my first T that had 35" tires running stock gearing.