Finally got around to putting in the rear Eibach sport shocks I had as well as lift blocks for the rear. Killed two birds and figured I would write it up for anyone who is interested.
It's a fairly easy job. Took me an hour total for both sides, you could certainly do it in less.
What you'll need:
23mm socket for lug nuts
21mm socket for all the bolts
Wrench to fit said sockets
21mm wrench or another socket
Jack stands or lift or something
Gloves, or not, your choice
So I had ordered the Eibach shocks all together in Dec on sale and rebate. The front have been excellent so was looking forward to the rear matching. So far they ride very nice, better than stock imo.
For the blocks and u-bolts, I took advice from @ssgjurista
and ordered GM parts that are commonly sold as take-offs from FS. Part numbers: 15885530 and 11569811
Which I have an extra set of the blocks if anyone wants to buy (pm me)
*note* This only the way I did everything. I am by no means a certified mechanic or authority. Wrench at your own risk and what you're comfortable with. I take no responsibility in your actions.
Step 1: Chock the front wheels and jack up the rear, rest the frame high enough on some jack stands or if you have a lift, even better.
Step 2: Use a jack under the diff to position axle as needed. To start, raise the jack so it's just barely carrying load. (should use a piece of wood or something instead of jacking directly on the diff)
Step 3: Remove the lower bolt on the shock. 21mm nut and bolt.
Step 4: Repeat on other side
Step 5: Remove u-bolt nuts on one side and loosen on other. 21mm nuts
Step 6: Take off axle seat (not sure what you call it) and lower jack slowly to lower the axle enough to slip the block under the springs. May need to jostle a little to free things up
Step 7: Replace u-bolts with longer set and put axle seat back on and tighten nuts, not fully yet
Step 8: Repeat for other side
Step 9: Remove top bolt for shocks. 21mm bolt
Step 10: Swap shocks and tighten the top bolts
Step 11: Use the jack to move the axle as needed to align the bottom bolts and tighten back up
Step 12: Torque everything back up!
Step 13: Put the wheels back on, lower the truck slowly and torque the lugs
Step 14: Clean up and enjoy your new ride!
Here are some extra pics. Definitely nice to have a nice warm garage with a lift and air tools...