| Re: 2.xx gears to 3.27 9 bolt gears
You need the same thing everybody else needs when they install a gear set.
It's commonly called a "gear install kit".
Has pinion bearings, carrier bearings, seals, all the shims you'll need for setting the gears up properly, new ring gear bolts usually, maybe a couple of other odds and ends. Plus, you'll need some fluid, and some fairly specialized tools, and some knowledge, so you don't risk destroying your gears.
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Numquam ponenda est pluralitas sine necessitate.
— William of Ockham, from Quaestiones et decisiones in quattuor libros Sententiarum Petri Lombardi
Roughly paraphrased into modern English, and applied to figuring out what's wrong with your car:
The simplest explanation that fits all the facts is probably the right one. | 
