Attachment III - Technical Information

OVERVIEW

This program involves replacing both front coil springs, performing a front end alignment and adjusting the head lamps. A Supplemental Safety Certification Label will also be installed which identifies revisions to Gross Axle Weight Rating (GAWR).

FRONT COIL SPRING REMOVAL

1. Remove the wheel and tire assemblies.





2. Remove the stabilizer bar brackets and the stabilizer bar. See Figure 1.

3. CAUTION: The axle must be supported throughout the procedure to prevent strain in the front brake hose.

Position suitable jacks under the front axles, then raise the jacks (or lower the hoist) to slightly compress the front springs.

4. Loosen the shock absorber upper retaining nuts to the top of the threads on the shock stud. Do not remove the nut.





5. Remove the upper spring retainers. See Figure 2.

6. NOTE: It is not necessary to remove the lower spring insulator, retainer or radius arm-to-axle bolt. The spring can be removed by rotating the spring slightly then lifting it off the seat.





Lower the jack supporting the front axles (or raise the hoist slightly) to take all the tension off the springs, then rotate and remove the springs from the vehicle. See Figure 3.

FRONT COIL SPRING INSTALLATION

1. Install the spring by rotating it over the washer and on to the seat.

2. Raise the jacks supporting the front axle (or lower the hoist).

3. Install the upper spring retainer and the bolt. Tighten the bolt to 30 Nm (22 lb-ft).

4. Tighten the shock absorber upper nut to 41 Nm (30 lb-ft).

5. Lower and remove the supporting jacks.

6. Install the stabilizer bar and the four (4) bracket bolts. Tighten the bolts to 25 Nm (18 lb-ft).

7. Install the wheel and tire assemblies.

8. Perform a front end alignment. Refer to Section 204-00 of the 2004 E-Series Workshop Manual for alignment procedure.

HEADLAMP ADJUSTMENT

NOTE:
This procedure should be performed AFTER the front end alignment.

NOTE:
There are various methods for headlamp aiming. Photometric or Mechanical aiming devices may be used according to manufacturers' instructions. Listed below are the instructions for performing the Screen Method, which requires no additional equipment except masking tape.

SCREEN METHOD AIMING

1. Before starting the headlamp adjustment:

^ check that the headlamps are clean.

^ check for correct headlamp operation.

^ check that the vehicle is on level ground.

2. NOTE: The vertical wall or screen must be a minimum of 2.4-meters (8-feet) wide.

Park the vehicle on a level surface approximately 7.6 meters (25 feet) from the vertical wall or screen directly in front of it.

3. NOTE: The center of the headlamp is marked on the center of the lens with a crosshair.

Mark a horizontal reference line on the vertical wall or screen as follows:

A. Measure the center of the headlamp height to ground and record the measurement.





B. Make a 2.4-meter (8-foot) horizontal mark (using masking tape) on the vertical wall or screen at the same distance from the around as previously recorded. See Figure 4.

4. NOTE: This procedure works best in a dark environment to effectively see the headlamp beam pattern.

Turn on the low beam head lamps to illuminate the wall or screen and open the hood.

5. On the wall or screen, locate the high intensity area of the beam pattern. Adjust the top edge of the high intensity zone even with the horizontal reference line.

6. In addition to the horizontal line marked in Step 3, a pair of vertical lines must be marked at the center line of the headlamps on the wall or screen as follows:

A. Mark the center line of the vehicle on the wall or screen.

B. Measure from the center of the headlamp to the center line of the vehicle and record the measurement.





C. Make two 1.5-meter (5-foot) vertical marks (using masking tape) on the wall or screen at the same distance from the center line as recorded in Step B. See Figure 5.

7. On the wall or screen, locate the high intensity area of the beam pattern. Place the left edge of the high intensity zone even with the vertical line corresponding to the headlamp being adjusted.

SUPPLEMENTAL SAFETY CERTIFICATION LABEL INSTALLATION

1. Locate and clean the area above the safety certification label on the driver's doorjamb. DO NOT remove the original label.





2. Install the new supplemental label on the vehicle above the existing label as shown in Figure 6.