Before you remove the lower A-arm, clean off a spot on the torsion bar just behind the A-arm socket and clearly mark the top of the torsion bar with paint or a marker. This is just to prevent confusion later if anything shifts or becomes misaligned.
Lower the jack from under the A-arm. Removing the jack will release most of the load from the torsion bar.
Note: If you can't get the jack out after lowering it, you can remove it after the torsion bar is unloaded.
If you want to weld on extra support, see Notes:A-Arm Reinforcement. This is not required, and not something I chose to do.
Install the grease fitting onto the side of the new lower ball joint, angled toward the rear of the A-arm so you can reach it later. Seat the lower ball joint grease boot onto the ball joint. There's a small indentation on the boot that should line up with the grease fitting.
Clean out the torsion bar socket on the new A-arm and apply a generous amount of chassis grease to the inside of the socket. Place the new A-arm near the coach in the correct orientation, ready to install. Be careful to keep dirt out of the ball joint and torsion bar socket.
Get under the coach at the rear of the torsion bar and measure how much the adjuster bolt sticks out of its special square nut. (There should not be any other nuts or Loctite on the adjuster bolt, though I ran into both.) The manual says to count turns, but I found it too easy to lose track while struggling with rusty stuck bolts and awkward access. Later GM manuals say to measure or "matchstick" (or "story stick", i.e. mark the length on something else.) You can also paint the bolt to mark it, but then you won't be able to clean the threads.
Note: Now is a good time to inspect the torsion bar and make sure you have a "right" bar on the right, and a "left" bar on the left. Some coaches have had a problem with this, resulting in an inability to properly set ride height. The bars should be stamped on one end with "L" or "R" and have an arrow indicating direction. It may not matter whether the stamp is at the front or rear, but the bars must be on the correct side.
Hold the new A-arm in the same orientation in which you removed the old one. Place the socket of the new A-arm over the end of the torsion bar and and seat the socket all the way onto the torsion bar. Work the arm back into the frame brackets. A small crow bar is useful for getting the holes aligned. Install the bracket bolts. Install the nuts but do not torque.
Note: If you decide to remove the torsion bar from the pork-chop for any reason, it's probably best NOT to apply any grease between the pork-chop and the torsion bar when you reinstall it. You don't want it to move out of the pork-chop.
Pull up the lower A-arm to about its normal height and put a jack under it. If you don't know what that height should be, hold up one of the shock absorbers to where it will mount as a reference.
Install the sway bar links and torque to 15 ft lbs.
While you have it out, clean and inspect the threads of the torsion adjusting nut and bolt. If you have a thread cutting tool, use it to clean up the threads. Apply a liberal amount of anti-seize or chassis grease to the threads. Use the torsion bar unloader tool to pull the pork-chop back up so you can fit the square nut into its slot. The indentations on the square nut face downward and rest on the crossbar edges. Install the adjusting bolt back to the same measurement it was before. Remove the unloader tool.© Copyright 2011,2012,2013,2014,2015,2016 K. Bradley