2004 GMC 2500 Step-By-Step Axle Gear Swap - Diesel Tech

13) The new outer pinion bearing, new pinion seal, and old driveshaft yoke were installed with a new pinion nut. Hustead torqued the new pinion nut with an air gun until the crush sleeve provided the correct bearing preload. The bearing preload was verified by using a torque meter calibrated in in-lb to measure the amount of drag on the pinion gear.

14) With the new pinion gear installed, Brusman moved on to replacing the ring gear. He removed the stock 41-tooth ring gear from the factory differential and replaced it with the new Yukon 41-tooth ring gear. Although both the old and new gears had the same amount of teeth, the new ring gear had a different pattern to mesh with the new 9-tooth pinion.

15) All the bolts holding the new ring gear in place were coated in thread-locking compound and torqued to 120 ft-lb.

16) The carrier assembly and bearing caps were then installed into the housing and torqued. The side bearing adjusters were then spun into position until there was zero backlash between the ring gear and the pinion. A special spanner wrench was required to make this adjustment.

17) Setting up the gears properly required two things. First, the gear-mesh pattern had to be verified, and then the backlash was checked. The goal was to visually verify that the pinion gear and ring gear meshed properly. Yellow marking compound was applied to a section of the ring gear, and the pinion gear was rotated to check the pattern.

18) When the pattern was confirmed to be good, the amount of backlash, or play between the two gears, was checked. A dial indicator was used to confirm that the backlash between the ring gear and pinion was adequate to allow for the gears to grow as they heat up.

19 It was important that the wear pattern was centered in the teeth in both directions. Brusman and Hustead were lucky as they nailed it on their first try, but sometimes the backlash or pinion shims would have to be adjusted to get the correct pattern.

20) The carrier cap bolts were retorqued one more time, and the tabs that lock the carrier bearing adjusters in place were installed.

21) Then, Hustead reinstalled the axleshafts and wheel center caps.

22) To give the rear differential a unique look, a ClearGearz cover was installed to show off the new Yukon gears and then filled with Royal Purple synthetic gear lube.

23) The front gear installation was completely different from the rear because it required the differential to be removed from the truck. The first step was to drain the oil from the differential.

24) To remove the front differential, Hustead unbolted the left and right axle halfshafts and the front driveshaft. A transmission stand was used to lower the differential out of the truck.