7 The JK ring & pinion set is used in the ProRock JK housing regardless if you’re using a standard 44 diff or the JK 44 diff. The JK gearset is different than a standard Dana 44 gearset. The pinion gear is shorter and has a larger diameter shaft. The JK pinion also rides on a bigger inner pinion bearing. The 8.8-inch JK ring gear is larger than a standard 44’s 8.5-inch-diameter ring gear. All JK high-pinion gearsets in front) meet on the driving side of the gear instead of the coast face of the gear (by far the stronger side of the gear).