There are some pretty hazardous conditions involved in getting the torque tube and the driveshaft dismantled. If you don't check the gear tooth contact pattern and duplicate it exactly on reassembly, you'll almost be guaranteed to create a gear whine- - - - -sometimes an extremely loud one, and the wear pattern the gears have established for decades will be incorrect. Wear on the gears will be accelerated as the mismatched tooth contact tries to establish a new running relationship. If you choose to remove the torque tube and carrier assembly from the axle housing, DO NOT dismantle the ring and pinion unless you also intend to install new gears in the process. The odds of reestablishing the exact backlash and tooth contact pattern on used gears is somewhere between slim and none.
Jerry
