1972 Firebird Trans Am Control Arms Upgrades

If you're leery of removing the front springs in the manner shown, a high-quality spring compressor, like this one from K-D Tools (No. 3450), can be used to compress the coil spring internally, prior to compressing the control arm with a hydraulic jack.

Because the coil spring is under pressure, it's extremely dangerous and must be decompressed slowly. Using extreme caution, the jack is slowly released, allowing the spring to unload to the point that it literally falls out. Quick unloading could cause the spring to fly out, inflicting damage to any nearby persons or vehicles.

With the coil spring out and set aside, the lower ball-joint nut is removed and the steering-knuckle assembly is lifted out.

Removal of the lower control arm follows. Using a 3/4-inch socket to hold the pivot bolt, the nut is removed using a 3/4-inch wrench. Some persuasion with a hammer may be required to tap both pivot bolts through the front crossmember.

The upper control arm is secured to its cross-shaft with large nuts at each end. They are loosened using a 15/16-inch wrench. The control arm can then be rotated upward exposing a portion of its retaining hardware.

The nuts securing the cross-shaft to the framerail are removed with a 3/4-inch wrench. A 3/4-inch socket can be used to prevent the corresponding bolt from spinning (but be careful, as the bolts are splined to the holes in the frame bracket to avoid spinning when loosening the nuts for wheel alignment). Note the exact position and amount of the original alignment shims sandwiched between the cross-shaft and framerail. They must be reinstalled during installation.

The cross-shaft bolts in the framerail are loosened by tapping on them with a hammer, which gains adequate clearance to extract the upper control arm from the vehicle. It otherwise maneuvers out with relative ease. This entire process was repeated on the other side of the T/A.

From all indications, our Trans Am's upper and lower ball joints appear to be its originals. Though the shaft of this lower ball joint wasn't loose in the housing, we see very little is left of its original grease seal. The ball joint will be replaced.

These photos tell the tale of the task. The lower control arm pivots about the bushing's center sleeve, which was once completely encased in rubber, looking much like the urethane replacement. We can clearly see the bushing is worn to the point that it no longer functions. The metal-on-metal contact proved the source of our abnormal squeak. While this bushing was by far the worst, the others were significantly worn, having an adverse affect our vehicle's alignment. In the next issue we'll rebuild the control arms by installing the new bushings and ball joints, and then we'll reassemble the front suspension.