Well, we've got answers, weather we can help or not is debatable. Just remember: We all own Jeeps, we've all sunk more money in them then we paid for them, and we're still spending more. We're probably insane:looney: Those off a Rubicon or are they on 15" rims? Tried a set of MT/Rs on my '00(stock take-offs from a 06 Rubicon). Not only was it a dog, but they were LOUD.
A close friend of mine(18 year dealership mechanic, does jeep work on the side) has this advice: All the aftermarket gears he's installed howl at least a little at some speed. ONLY buy factory gearsets if you want a quiet axle. That means Dana gears in the front, and (probably for you)Chrysler in the rear. It seems the OEMs use a extra/final honing step in the machining process that results in a better mesh. Prepare to be SHOCKED at the price(specially the Chryco stuff). A couple days after he told me that, I saw the same advice on Randy's Ring&Pinion website. The other bad news(besides price)is the factory gearsets only go down to 4.10. If you want to gear any deeper, you have to go aftermarket.
Now for the good news: It probably won't matter to you.
If you are going to stick with the MT/Rs or a similar tire, any good gear set will be OK. No matter how much noise the gears make, the tires are going to be louder and mask the sound. You'll never notice the axle noise unless you change to an AT- or street tire.
As for ratios, Chrysler puts 4.10s in the jeeps with 32"s from the factory, and that will give about stock performance. If you are SURE you're never going to 33"/35"s, the 4.10s are OK. If you even think you might want bigger tires later, go to 4.56. I won't recommend the 4.88s for the stock front axle(my personal opinion) but you probably won't break it if you stay off the rocks.
You are also going to need a new dif. carrier for you front axle when you re-gear. If you want a front locker, now's the time
