Question on Rear Stabilizer Bar: The PIM states to install shims as required. The Service manual really does not say much or I missed it. Am I looking to just fill the gap or is there a spec. I am looking for?

Question on Torqueing Control Arms. I do understand and will wait to torque the control arms until the total weight is on the wheels. I would just like to understand the theory behind this. What did they do on the Oldsmobile line as I would think these parts where installed near the beginning of assembly. Was there a final torque station at the end of the assembly line?

 

Jim,

The purpose of the shims is to prevent imparting any side load on the lower arms, which could lead to buckling. This is not a critical measurement. Loosely bolt the rear bar in place and push it all the way towards one arm. Select shims as needed to fill the gap to the other arm without forcing them in (which would induce a buckle in the opposite direction). Now split the shims as evenly as possible between the two sides and torque the sway bar mounting bolts. It is not necessary to perfectly split the shims side-to-side, so don't worry too much about that.

The reason for torquing the bolts through the bushings with the suspension at ride height is that the bushings are actually rubber torsion springs. When you torque the mounting bolts, it clamps the bushing in a "zero clocking" position. Any suspension movement from that point imparts a torque into the rubber bushing. To minimize this additional spring force and to prevent premature deterioration of the rubber, you want to torque the bolts and thus clamp the bushings at normal ride height. This minimizes deflections on the rubber and also ensures that deflections will average out, with both up and down motion of the suspension. If you torqued the bolts with suspension at full droop (ie, with the car on a lift), the rubber would only be distorted in one direction over the life of the car.

 

Thanks Joe,
That all makes sense.