Raise the rear of your Chevy off the ground with a jack and position a set of jack stands under the axle housing. Lower the jack and allow the truck to settle onto the jack stands.
Locate the four retaining bolts on the pinion flange and remove them with a wrench. Pull the drive shaft back and remove the u-joint from the yoke then set the drive shaft aside.
Locate the large nut in the center of the pinion yoke and match mark it to the end of the pinion shaft with a paint marker. Place a torque wrench on the nut and note the force require to turn the nut. Remove the nut from the pinion shaft with a large breaker bar and socket, you will need to set the parking break securely to do this.
Slide the pinion yoke off the pinion shaft and set it aside. Using a small flat screwdriver, bend the outer metal ring of the seal to help loosen it then pry it out of the bore. Pack the cavity behind the seal with lithium grease then install the new seal into the bore.
Drive the seal into the bore with a seal driver and hammer than slide the yoke back onto the pinion shaft, making sure the marks you made on the yoke and shaft align. Install the pinion nut and tighten it, seating the yoke on the shaft.
Tighten the nut with a torque wrench, using the torque reading you took before removing the yoke as your guide. Position the u-joint on the drive shaft back in the yoke and install the retaining bolts. Tighten the bolts with a wrench.
Raise the rear of the truck off the jack stands with a jack, remove the stands from under the truck then lower it back to the ground.
I copied and pasted. Im lazy
I know that damn pinion nut is a BIATCH sometimes to get off. I use the upper half of my jack handle and came out the side of the fenderwell to break it loose.
2001 HD 8.1L 4x4 Crew SB LT
EFI Live, K&N CAI, MSD, Plug mod (in testing), 160* T-Stat, Flomaster 40 Series SS (Duals)(No tails), Custom H-Pipe, (2) RF P2410's in custom down fire box, Rockford Old Skool 250aii amp, AirLift bags, On board compressor, Custom mount gauges, Body colored trim, 285 Revo ATV's, 16x10 Ions, 6K HID Lows & Fogs, Blue LED Dash, Blue LED Switches, Blue LED Footwell Lights, Blue LED Interior Lighting, and so much more....
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