In a Mopar front suspension, the lower control arms are like heavyequipment on a job site. They transfer all the torsion bar's force andactually hold the car up, while the strut rods handle the fore and aftforces. The upper control arms locate the uprights and swing along forthe ride. When Mopars are equipped with a sway bar--you guessed it--theytie into the lower control arms. If performance handling is the goal,the lower control arms had better be in top condition.
What can go wrong with such a simple looking chunk of metal? There's noquestion the first thing to blow out of a Mopar front suspension is alsothe toughest part to replace: the lower control-arm bushing. When thebushings go, accurate control and handling go with it. The lowercontrol-arm bushing is the only replaceable "wear" part on the arm, butit is also the most critical bushing in the suspension. We've got sometricks to make the nasty job of replacing it easier.
We're in the process of building a hot-handling E-Body, which will see ahost of suspension and braking upgrades up front. When we heard our palsat AR Engineering had fabbed-up reinforcements to beef up the lowercontrol arms, it made perfect sense to investigate it further. The ARpiece boxes the open lower section of the arms, and the prospect ofadded strength to these highly-stressed units got our attention. Afterall, looking at the stock control arms, it is clear by the beefyvertical section that they are built to take an enormous amount ofloading in a vertical plane--no surprise, since the major loading isvertical, supporting the vehicle's weight. Now think about a fat swaybar linked in front of the arms' centerline. What we now have, inengineering terms, is a torsional moment; the sway bar forces want totwist and distort the control arm. Our plans included a fat aftermarketfront sway bar, and any extra muscle we could add to the arms would bewelcome.
1. Rebuilding your front suspension? Here's usually the mostdifficult part to get right--the lower control arm. The lower control armpivots on the pivot shaft (left). The pivot shaft bolts solidly to theK-member and doesn't budge, while the torsion-bar socket rotates withthe control arm. Torsional deflection in the lower control arm's innerrubber bushing is the only thing that lets it rotate for suspensiontravel. Replacing the lower control-arm bushing is the number-one sourceof misery in rebuilding a Mopar frontend, unless you know the tricks. |
2. The pivot shaft comes out first, and removing it is simply amatter of pressing it out from the back through the torsion-bar socket. |
3. The shaft will come out with the inner bushing shell stillattached. It's a tight press fit. With a hammer and chisel, make fourgrooves along its length 90 degrees apart. Marking it this way willrelieve the press fit, and the shell will usually slide off by hand. |