Lower A-Arms
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.
Install the torsion bar unloader tool as described in the manual and tighten it to take the load off the adjustment bolt. Remove the adjustment bolt and the big square nut. Unscrew the unloader tool so the small end of the pork-chop can move down freely a couple of inches below the frame. This releases all remaining load and makes it easier to get the A-arm onto the torsion bar. You're NOT trying to remove the torsion bar, just making it free to move.
Get back out from under the coach. Remove the frame bolts from the lower A-arm and pull the arm out of the frame brackets. A small crowbar may help. Pull the arm toward the front of the coach to slide its socket off the end of the torsion bar. A few taps with a mallet may help get it move. Clean the inside of the frame brackets and the end of the torsion bar and apply fresh grease.
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.
At the back of the torsion bar on the crossmember where the pork-chop is located is a round inspection hole. Look in this hole to make sure the torsion bar is still fully seated into the pork-chop. If it's not, move the torsion bar toward the rear of the coach until it's flush with the back of the pork-chop.
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.
Torque the lower A-arm frame bolts to 85 ft lbs.
Note: If you can't torque the bolts, they're stripped or have the wrong size nuts. That's why you should torque these here -- so you don't have to unload everything to get the bolts back out.
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.
IMPORTANT NOTE: The pork-chop adjuster bolts should be installed so they are equal on both sides. If one pork-chop is held higher than the other, the front load will be unbalanced. This can result in one side being dangerously overloaded, and will affect handling. The rear suspension has a profound effect on the front ride height. When measuring and setting the front height, it is important to first block the rear of the coach to the correct height and then deflate the air bags so they don't apply pressure to the front suspension. When adjusting the front height, try to keep both bolts set close to the same number of turns.
If your kit contains a steering stop bracket, install it on the rear bolt that holds the ball joint to the lower A-Arm. This stop is used with knuckles that were made in 1989-94 because they lack the stop that was molded into later knuckles. The bracket can be mounted above or below the A-Arm. Reinstall the bolt and torque the nut to 45 ft-lbs.
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