PRIMAAX
®
EX / PRIMAAX
®
for Volvo Vehicles
17730-254
23
Alignment & Adjustments
SECTION 7
Alignment & Adjustments
RIDE HEIGHT ADJUSTMENT
The Volvo PRIMAAX EX / PRIMAAX suspension is equipped with a height control valve located
on the front drive axle. The height control valve is not supplied by Hendrickson, although it is a
required component. Hendrickson is not responsible for components supplied by the vehicle
manufacturer. For assistance with inspection, adjustments, maintenance, replacement and
rebuild instructions on these components, refer to the vehicle manufacturer.
LATERAL ALIGNMENT
1. Use a work bay with a level surface.
2. Relax the suspension by slowly moving the vehicle back and forth several times in a straight
line without using the brakes. This will slacken or loosen the suspension as the vehicle is
positioned. End with all wheels positioned straight ahead.
3.
DO NOT
set the parking brake. Chock the front wheels of the vehicle.
4. Verify and maintain the air system at full operating pressure.
5. Verify the vehicle is at the correct ride height. Correct as necessary. Refer to Ride Height
Adjustment in this section.
6. Verify all suspension components are in good condition. Repair or replace any worn or
damaged suspension components before proceeding with the alignment process.
7. Ensure all drive axle tires are the same size and properly inflated.
8. Measure from the outside of the frame rail to the rim flange of the inner tire. Record the
measurement.
9. Measure the same distance on the opposite side of the same axle. Record the measurement.
10. Subtract the two measurements to get a difference between the two. If the difference is
greater than Hendrickson recommended
1
/
8
" (3 mm), it will be necessary to correct the lat-
eral alignment. Adding or removing shims that are located between the transverse torque
rod and frame rail accomplishes this.
■
A general rule of thumb is to use a shim with a thickness that is half of the difference
between the two measurements.
EXAMPLE
If the lateral alignment is out of specification by ¼" (6mm), remove or install a
1
/
8
" (3 mm)
shim between the transverse torque rod and frame rail or between the torque rod and axle
tower as needed.
NOTE
Hendrickson recommends the use of Grade 8 bolts and Grade C locknuts be used for all torque
rod attachments.