Service Procedure
# SERVICE PROCEDURENOTICE:
Disregard instructions enclosed in kit P/N # 15624685. Use procedures listed in this Service Procedure instead.
# PRELIMINARY INSPECTION OF THE CONTROL ARM
# 1. Raise left front of vehicle and support with suitable safety stands.
# 2. Inspect left hand lower control arm to determine if subject vehicle requires modification. Arms subject to kit installation will have a small radius of 0.1 inch (2.54 mm) at flange-to-nose transition (Figure 1) instead of the intended 1.0 inch (25.4 mm) nominal radius (Figure 2). All right hand lower control arms have proper radius and may be used for comparison.
NOTICE:
Some 1985 and 1986 vehicles may have had their lower control arms replaced. If inspection of left hand lower control arm indicates 1.0 inch (25.4 mm) nominal radius as shown in Figure 2, control arm does NOT require reinforcement kit. If this is the case, install a Campaign Identification Label and submit a Product Campaign Claim for "Inspect Control Arm - No Action Required".
# INITIAL POSITIONING OF THE REINFORCEMENT
# 1. Clean left hand lower control arm of all dirt, rust, grease and undercoating from spring pocket outboard. Clean both top and bottom areas of the control arm. This will ensure good mechanical contact of reinforcement and U-bolt to control arm and ball joint flange. Use appropriate solvents and/or a wire brush as required.
Notice:
If control arm and reinforcement are not thoroughly cleaned, the U-bolt may "walk" off the bottom of the ball joint when it is tightened.
# 2. Center reinforcement (Figure 3B, "1") between flanges. Gaps A & B shown in Figure 3B are to be equal within 0.060 inch (1.5 mm). Secure reinforcement with a 4", 5" or 6" C-clamp (Figure 3).
NOTICE:
Reinforcement is designed to fit ball joints with a bottom diameter of 2.60 inches (66 mm) or greater, and is installed CORRECTLY when ball joint makes full contact with reinforcement radius (Figure 3B), not just center section of reinforcement.
Technicians may find that ball joint does not make full contact with radius of reinforcement when reinforcement is centered between flanges. In this event, it is possible that an aftermarket ball joint with a bottom diameter which is less than 2.60 inches (66 mm) has been installed. This does not allow for full contact with radius of reinforcement and, when this happens, only a small section of ball joint will be centered on reinforcement.
If this occurs, make certain ball joint is clean as described in Step 1 and then measure bottom diameter of ball joint with calipers. If measurement is LESS THAN 2.60 inches (66 mm), ball joint must be replaced with a Genuine GM ball joint.
# 3. Install U-Bolt (Figure 3, "7") and torque to approximately 10 N-m (7 lb.ft. ).
NOTICE:
THIS STEP MUST BE PERFORMED BEFORE PROCEEDING TO STEP 4.
When correctly installed, U-bolt will be about even with bottom of ball joint. U-bolt is NOT designed to fit into galley of control arm. On some vehicles U-bolt may contact flange edge of control arm and interfere with correct installation. In these cases you may remove only enough material (LIGHTLY grind) (Figure 3A) from outer radius of U-bolt to allow clearance between U-bolt and control arm (Figure 3, "7").
4. Drill center hole with 3/8 inch (9.5 mm) drill. Reinforcement (Figure 3, "1") has been designed to be used as a drill guide. Keep drill as perpendicular as possible when drilling.
5. Install one 3/8-16 bolt (Figure 3, "6"), nut (Figure 3, "3") and washer (Figure 3, "2") in center hole and torque to approximately 18 N-m (13 lb.ft.).
6. Remove "C" clamp.
7. Drill three remaining holes in any sequence.
# 8. Disassemble reinforcement (Figure 3, "1") and U-bolt (Figure 3, "7") from control arm and remove all chips or burrs from reinforcement.
INSTALLATION OF REINFORCEMENT
# 1. Reinstall reinforcement (Figure 4, "1") and U-bolt (Figure 4, "7"). Hand start all bolts. Tighten U-bolt nuts (Figure 4, "5") to approximately 22 N-m (16 lb.ft.). Make sure U-bolt is ALIGNED with bottom edge of ball joint and is NOT COCKED while continuing to torque.
NOTICE:
If rear most bolt head flange interferes with bump stop bracket, install bolt from bottom of control arm.
# 2. Torque 3/8-16 bolts (Figure 4, "6") to 37-43 N-m (27-32 lb.ft.). Tighten center bolt first and remainder in any sequence.
# 3. Torque U-bolt nuts (Figure 4, "5") to 40-46 N-m (30-34 lb.ft.).
# 4. Lower vehicle.
5. Install Campaign Identification Label.