1.1 Air Suspensions Inspection & Maintenance

1. Leaking Air or Restricted Air Flow

• If both sides are flat, there may be a leak between the air brake system and the suspension air system.
• If flat on one side, there may be a leak between the height control valve and the air spring.

2. Automatic Height Control Valve

• Test it: disconnect linkage and move actuating arm up and down to see if air bag inflates / deflates.

3. Bushings

• Place pry bar between trailing arm and hanger and check for movement. Abnormal tire wear is a good indicator of bushing wear.

4. Shocks

• Should be warm to the touch after vehicle operation
• If cold, the shock is not functioning properly and should be replaced.
• If the shock can be easily compressed after removal, the shock should be replaced.
• Check for shock bushing wear

5. Under-Inflation

• Slight positive pressure maintains shape of the air bag and prevents folding/pinching.

6. Causes of Air Spring Failure

• Overextension
• Abrasion
• Contamination
• Suspension misalignment
• Road hazards
• Fatigue / old age