AirLiner Suspension
Warning: Do not replace individual leaves of a damaged leaf spring assembly; replace the complete spring assembly. Visible damage (cracks or breaks) to one leaf causes hidden damage to other leaves. Replacement of only the visibly damaged part(s) is no assurance that the spring is safe. On front spring assemblies, if cracks or breaks exist in the two top leaves, a loss of vehicle control could occur. Failure to replace a damaged spring assembly could cause an accident resulting in property damage, serious personal injury, or death.
Important: To prevent voiding the warranty on Barksdale height-control valves, note the following:
-
Do not overtighten the bolts in the Barksdale height-control valve housing. The bolts should not be loose, and should not require tightening. Only if necessary, tighten the valve housing bolts 45 lbf·in (500 N·cm). Any damage to the valve housing will void the warranty.
-
Do not attempt to disassemble the Barksdale valve body or the control lever. There are no serviceable parts in the valve, and any disassembly will void the warranty.
Notice: When removing or loosening a Barksdale height-control valve from a mounting bracket, always hold the valve-side mounting studs in place with an Allen wrench while loosening or tightening the nuts that attach the valve to the bracket. Because the mounting studs are threaded into the valve body, loosening the nuts without holding the studs can tighten the studs, which can crush the valve body and damage the valve. Conversely, tightening the nuts without holding the studs can back the studs out, causing a separation of the two halves of the valve body, and possibly a leak.
- Inspect the fasteners that attach the suspension brackets to the frame for proper torque. See for bolt torque specifications.
- Inspect the forward and rear spring brackets for wear, cracks, and other damage. If any of these conditions exist, replace the damaged bracket(s).
- Inspect the crossmember(s) and gussets for wear, cracks, and other damage. If any of these conditions exist, replace the damaged parts.
- Visually check the air spring piston for cracks, chips, and broken areas. Check the air bag for rips, tears, and holes. Verify that the air spring assembly does not leak.
- Park the vehicle on a level surface, using a light application of the brakes. Do not apply the parking brakes. Shift the transmission into neutral, and build the secondary air pressure to at least 100 psi (690 kPa). Shut down the engine.
- Mark the location of the front and rear tires on the floor, and chock the tires on one axle only.
- On single-drive rear axle configurations, measure the distance
from the bottom of the left axle stop to the top of the U-bolt pad.
On dual-drive rear axle configurations, measure the distance from
the bottom of the forwardmost left axle stop to the top of the axle
U-bolt pad. See Fig., Ref. A. The correct distance for single and dual-drive rear axles
is from 2-3/8 to 2-7/8 inches (60 to 73 mm).
-
Measure height here.
-
Left Forwardmost Axle Stop
Fig. 1, AirLiner Axle Stop Measurement
-
- If the axle stop measurement is not correct, contact your Western Star dealer to adjust the leveling valves.
- Check the shock absorbers. For instructions, see Front Suspension Check, "Suspension Inspection."
Warning: Be sure that the fasteners are torqued correctly. Fasteners that are not tight can cause separation of components or premature failure of components, loss of vehicle control and possible personal injury or property damage.
Warning: Replace worn, cracked, or damaged spring brackets. Failure to do so could result in bracket breakage, possibly leading to loss of vehicle control and resulting in personal injury or property damage.
Warning: If damaged air bags are found, do not continue to use the vehicle, take the vehicle to your Western Star dealer to have the air bags replaced because the sudden loss of air bag pressure can cause loss of vehicle control resulting in serious personal injury and property damage.
Important: Before checking the AirLiner suspension height, make sure there is no load on the chassis, and the trailer is unhitched.