With the housing strengthened, the next logical place to put your money is in axle gearing. Upgraded gearing resolves the most common issue associated with the factory Dana 30/44-running larger tires. With the stock 3.55:1 gearing, the model X JK is limited to a 33-inch-tall tire; any bigger and the vehicle becomes super-sluggish off the line and is basically undrivable around town. We opted for a set of 4.88:1 gears from Superior Axle & Gear because we planned to run 37-inch rubber on this rig. Superior's ring and pinion sets are manufactured from premium 8620 steel material with precise tolerances to improve gear contact and set-up. Heat treatment ensures that Superior's gearsets last the life of the vehicle while balancing the need for shock load deflection. We like the fact that they come with a two-year warranty against manufacturing defects.