Premier vehicles are the only vehicles covered by this information which utilize a torsion bar rear suspension system.
Since torque is developed at different angles, the rear torsion bars at each side of the vehicle twist in different directions. The bars are machined differently and must be installed at the correct location in the rear suspension. The left side bar is identified by the letter G stamped twice on its outer end. The right side bar is identified by the letter D stamped twice on its outer end. In addition, the outer end of each torsion bar has 31 splines and the inner end has 30 splines. The torsion bars have a dot stamped onto their outer ends to assist in end identification and installation reference. This end with the dot must always be installed facing outward.
The front and rear torsion bars serve different purposes these vehicles. The front torsion bar is the actual suspension component, while the rear is used mostly as an anti-sway bar. The front bar is 26.25 in. (66.7cm) in length. The rear bar is 23.26 in. (59.1cm) in length. Also, the rear torsion bar in a vehicle is dependent upon the suspension package originally installed on the vehicle. The bars are color-coded to identify its diameter. The color codes are as follows:
Never raise a Premier with a lift positioned under the V-shaped rear crossmember. Never let the hoist arms come into contact with the lower edge of the rocker panel. If necessary, place a small block of wood between the hoist pad and the body lifting points so the vehicle does not rest on the rocker panels. The manufacturer does not recommend use of a twin post under-the-vehicle hoist.
REMOVAL & INSTALLATION
See Figures 1, 2, 3, 4, 5, 6, 7 and 8
Special Tools 6049 (Suspension Arm Positioning Tool) and 7466 (Spacer) will be needed for installation of the torsion bars. Extreme care should be exercised when performing this operation.
- Disconnect the negative battery cable.
- Raise the vehicle and support safely.
- Remove the both rear wheels and shocks.
- Pry the protective end caps and remove them from the front torsion bars.
- Unthread the protective end caps and remove them from the rear torsion bars.
- Pry the retaining clips away from the ends of the torsion bars and remove the clips.
Each torsion bar bracket has an existing dot stamped into it that provides a reference for the initial installation position of the front torsion bar. An additional installation position mark must be punched into the trailing suspension arm before the bar is removed from the crossmember.
- Place a straightedge on the centerline of the 2 torsion bar installation holes and punch a dot into the trailing suspension arm adjacent to the rear torsion bar spline groove.
- Note and record the relative positions of the installation reference dots on the ends of the torsion bars in respect to the dots on the torsion bar support bracket and the trailing suspension arm. In other words, count the number of splines between the dot on the bar and the dot made on the bracket or trailing arm. These dots will ensure that the proper "initial twist'' is applied to the torsion bar upon installation, according to the suspension package originally installed in the vehicle.
- Loosen and extract the front torsion bars using a slide hammer. Pull the bars out far enough to disengage the splines from the connecting link and the torsion support brackets.
- Loosen and extract the rear torsion bars using a slide hammer. Pull the bars out far enough to disengage the splines from the connecting link and the trailing suspension arms.
- The crossmember must be lowered before the torsion bars can be removed from it. Using the proper equipment (hydraulic jack), support the weight of the rear crossmember. Do not apply lifting force to the crossmember.
- Loosen both torsion support bracket front bolts approximately 4 turns. Do not remove these bolts.
- Loosen both torsion support bracket rear bolts approximately 10 turns. Do not remove these bolts.
- Slowly allow the torsion support bracket and crossmember to lower about 1 in. (25mm).
- Remove the torsion bars and connecting link from the crossmember.
- Make sure the correct torsion bar will be installed to the correct side- G is stamped on left side bars; D is stamped on right side bars.
- Insert the torsion bars into the rear crossmember. At this time, do not insert it so far as to engage the torsion bar splines with the splines in the support brackets or suspension arms.
- Raise the crossmember and torsion support bracket and tighten the attaching bolts to 68 ft. lbs. (92 Nm).
Before the torsion bar splines are meshed with the connecting link splines, the torsion support bracket splines and the trailing suspension arm splines must be positioned at the correct location in relation to the vehicle chassis.
- Position the trailing suspension arms in the correct location on each side of the vehicle using 2 sets of special tool 6049 (threaded rod). Two spacers from tool set 7466 must also be used. Adjust each positioning tool so the distance between the center of the rod eyelet and the center of the hub on the adjusting bracket is 17 15 / 16 in. (45.6cm).
- After the distance has been properly set, install the positioning tools where the rear shocks are installed.
- Insert the upper attaching bolt through the eyelet and loosely tighten it. Insert the spacer into the lower shock attaching bolt hole and insert the adjustable bracket hub into the spacer.
- Liberally apply all-purpose lubricant to all torsion bar splines.
If the bars are not being replaced, they must be installed in their exact original locations. The dot reference positions must be the same on both sides of the vehicle to prevent added stress from being applied to the bars.
- Refer to the previously made torsion bar dot reference positions and correctly mesh the splines of the torsion bars with the trailing suspension arm splines.
- Mesh the connecting link splines with the splines of the previously positioned rear torsion bar so the connecting link is correctly centered within the V-shaped channel in the rear crossmember. Use large pliers to assist in this operation if necessary.
- Mesh the splines of the opposite rear torsion bar with the trailing suspension arm splines and the connecting link splines.
- Mesh the splines of one of the front torsion bars with the torsion support bracket splines and the connecting link splines.
- Mesh the splines of the opposite front torsion bar with the torsion support bracket splines and the connecting link splines. Recheck all bars for correct re-installation.
Do not directly contact the splined ends of the bars with a hammer because this could damage the splines.
- After all 4 bars have been installed, the ends must be centered in the torsion support brackets and the trailing suspension arms. Tap on the ends of the front torsion bars using a hammer and brass drift to position. Adjust so the outer end of each bar is recessed 0.750-0.875 in. (19.0-22.2mm) from the outer edge of the torsion support bracket boss.
- Tap on the ends of the rear torsion bars using a hammer and brass drift to position. Adjust so the outer end of each bar is recessed 0.188-0.312 in. (4.7-8.0mm) from the outer edge of the trailing arm.
- Position and press the retaining clips inward against the ends of the torsion bars.
- Install the protective caps to the end of the torsion bars.
- Remove the positioning tools from the vehicle and install the shock absorbers. For more details, refer to the installation procedure later in this section.
- Install the wheels and tighten the lug nuts until snug, then lower the vehicle to the ground.
- Once the vehicle weight is resting on the wheels, tighten the lug nuts to 63 ft. lbs. (85 Nm) on steel wheels and to 90 ft. lbs. (122 Nm) on aluminum wheels.
Measure the vehicle height using the following procedure:
- The vehicle should be unloaded, on a flat level surface, with a full tank of fuel, and with the tires all adjusted to the same proper pressure.
- Measure from the centerline of the front wheel hubs to the ground (H1) and from the rear wheel hubs to the ground (H4).
- Measure from the engine cradle at the wheel hub vertical centerline to the ground on each side (H2).
- Measure from the front torsion bar horizontal center line to the ground on each side (H3).
- Subtract H2 from H1. This value should be 3.36-3.98 in. (85-101mm). If this height is not within specification, replace worn front end parts.
- Subtract H3 from H4. This value should be 1.25-1.87 in. (31.5-47.5mm).
- If the rear vehicle height is not within specification, reposition the front torsion bar(s). This is accomplished by adjusting the length of special tool 6049 (threaded rod) when re-installing the bar. Do not attempt to adjust vehicle height with the rear torsion bars.
- Connect the negative battery cable and road test the vehicle.